The Definite Article

Verbs

German verbs can be classified as weak or as strong. Weak verbs are very regular in their forms, whereas strong verbs change the stem vowel.
Weak:

kaufen, kaufte, gekauft

Strong:

singen, sang, gesungen

With its Anglo-Saxon origin, this notion is also present in English.

flip, flipped, flipped
sing, sang, sung

Some German verbs have weak and strong forms. This may depend on meaning:

Der Botschafter wurde nach Berlin gesandt.
Der Süddeutsche Rundfunk sendete ein Konzert aus dem Gasteig.

Or on transitive vs. intransitive use:

Das Hemd hing auf der Wäscheleine.
Sie hängte das Hemd auf die Wäscheleine.

Separable Verbs

Sometimes you will run into verbs such as anrufen, aufräumen, mitkommen. These verbs are examples of Separable Prefix Verbs. When you see these kinds of verbs, it will have a preposition prefix followed by a verb. These verbs separate when they are the main verb of a sentence.
EXAMPLES:
I am calling the butcher. Ich rufe den Metzger an.
I am trying on the boots. Ich probiere die Stiefel an.

Reflexive Verbs

Reflexive Verbs are verbs involving the reflexive pronoun “sich” and its conjugations that reflect, or refer back, to the performer of the action. There are only accusative and dative reflexive pronouns.
Accusative reflexive pronouns are used when there is no direct object. Dative reflexive pronouns are used when a direct object is present. However, when using a direct object, the possessive is not used.
Examples:

Accusative: Ich verletze mich. I injure myself.

Dative: Ich verletze mir die Hand. I injure my hand.

Accusative: Er hat sich verbrannt. He burned himself.

Dative: Er hat sich den Daumen verbrannt. He burned his thumb.

Modals

Dürfen

Dürfen means to be allowed/permitted, may.
Present tense:
Ich darf – I am allowed to
Du darfst – You are allowed to
Er/Sie/Es darf – He/She/It is allowed to
Wir dürfen – We are allowed to
Ihr dürft – You (plural) are allowed to
Sie dürfen – They are allowed to/You (formal) are allowed to
Darf ich einen Freund zum Fest bringen? May I bring a friend to the party.
Man darf hier nicht rauchen. You’re not allowed to smoke here.
Past tense:
Ich durfte
Du durftest
Er/Sie/Es durfte
Wir durften
Ihr durftet
Sie durften
Niemand durfte die Stadt verlassen. No one was allowed to leave the city.

Können

können means ‘to be able, capable’. It is cognate with the English word ‘can’/’could’.
Present Tense:
ich kann – I can
du kannst – You can
er/sie/es kann – He/She/It can
wir können – We can
ihr könnt – You can
sie können – They can
Ich kann das nicht tun. I can’t do it.
Past Tense:
ich konnte
du konntest
er/sie/es konnte
wir konnten
ihr konntet
sie konnten
Wir konnten sie nicht erreichen. We could not reach them.

Mögen

mögen expresses a pleasure, or desire. In the present tense, it is used transitively with people or food. e.g. ‘Ich mag dich’ ‘I like you’ or ‘Ich mag Erdbeeren’ ‘I like strawberries’. The subjunctive (of the past) expresses preference to perform the action of a subordinate clause ‘Ich möchte nach Frankreich reisen’ I would like to travel to France’. ‘mögen’ is cognate with the English verb ‘may’/’might’.
Present Tense:
ich möchte/mag I would like to
du möchtest/magst You would like to
er möchte/mag He/She/It would like to
wir möchten/mögen We would like to
ihr möchtet/mögt You would like to
sie möchten/mögen They would like to
Ich möchte nach Deutschland reisen. I would like to travel to Germany.
(There is also a present subjunctive möge, which is very formal:
Der König sagte: “Er möge eintreten.” – The king said: “He may enter.”)
Past Tense:
ich mochte
du mochtest
er/sie/es mochte
wir mochten
ihr mochtet
sie mochten

Müssen

müssen expresses something forced on you. It is etymologically related to ‘must’.
Present tense:
ich muss gehen I must (have to) go
du musst
er/sie/es muss
wir müssen
ihr müsst
sie müssen
Past Tense:
ich musste I had to
du musstest
er musste
wir mussten
ihr musstet
sie mussten
Note that the negative nicht müssen is not the English must not, but rather need not or don’t have/need to. must not translates to nicht dürfen.
Ich muss nicht arbeiten. ~ Ich brauche nicht zu arbeiten. I don’t have to work.
Ich darf nicht arbeiten. I must not work.
There are however some northern German uses like: Du musst das nicht tun meaning Du solltest das nicht tun.

Sollen

sollen expresses an obligation or duty. It is etymologically related to ‘shall’.
Present tense:
ich soll schwimmen I am to swim
du sollst
er/sie/es soll
wir sollen
ihr sollt
sie sollen
Past Tense:
ich sollte I was to
du solltest
er sollte
wir sollten
ihr solltet
sie sollten

Use in Perfect (and Pluperfect) Tense

Although all these modals have a normal perfect:
gedurft gekonnt gemocht gemusst gesollt
in connection with other verbs, the infinitive form is used:
Ich habe das tun dürfen – können – mögen – müssen – sollen.
Falsch ist:
Ich habe das tun gedurft – gekonnt – gemocht – gemusst – gesollt.
Das gilt auch für die Verben sehen und hören:
Ich habe ihn kommen sehen – hören.

Use of modal verbs as full verbs

Modal verbs can be used as full verbs indicating motion.
Er muss nach Berlin He must go to Berlin.

Present Tense

Use

The Present Tense is used for..

• The Present Tense (=”das Präsens”) is used to describe situations that are happening and aren’t the past.

• For Ongoing Action, like I’m swimming in the pool now

• Everyday Truths, like The moon and stars will come at night.

• Future meaning, if explictly stated, like I will run tomorrow morning

• Actions started in the past and still going on in the present I’ve been cleaning the house all day

Progressive Forms

There is a present progressive tense in colloquial spoken German. Its use is optional.
Here is one example:
Ich bin am Fahren. (I am at the driving) I’m driving.
The person to say this would be driving during the time they say this and they would continue to drive after stating this for some time.
You nominalize the verb (“fahren” (driving) becomes “das Fahren”) and add a “am”. You can also du this with forms of the past.
Als er kam war ich gerade am Abwaschen. (When he arrived i was at “the dishwashing”) I was washing the dishes when he arrived.
So the verb “sein” (to be) includes the information what tense he was doing what he did in.
Here the progressive meaning is also emphasized with the word “gerade” meaning something like: I was JUST ABOUT to wash the dishes(not the same though because it means he is already doing it and not about to start).

Perfect Tense

The Perfect Tense or das Perfekt of verbs is used to talk about things in the past which have already happened. It is sometimes referred to as “Present Perfect Tense”. This can cause confusion. While the formation is similiar, the meaning and usage differs.

Formation

As in English, the perfect tense consists of two parts. An auxiliary (Hilfsverb) and a past participle (Partizip Perfekt). Compare the examples given below with their English translations.

Past participle for regular verbs

The general rule is simple:

There are some groups of regular verbs that slightly differ from that pattern.
Some verbs drop the prefix ge-. Like the other regular verbs they end in -t. These are:
1. Verbs with unseparable prefixes (be-, ent-, er-, empf-, ge-, ver-, miss-, zer-)
Examples:

2. Verbs ending in -ieren
Examples:

3. Another group is formed by verbs with separable prefixes
With separable verbs, the prefix ge is placed between the prefix and the rest of the verb.
Examples:

Separable and inseparable verbs are distinguished by the stressed syllable:

Er hat das Buch ins Chinesische übersetzt.
Der Fährmann hat den Passagier übergesetzt (über den Fluss gesetzt).

Past Participle for Irregular Verbs

Irregular verbs always end in -en. The vowel can be different from the one in present tense. Look at some examples:

You have to learn these forms by heart. How you can obtain the necessary information and how you should learn them is described in section tips for learning below.
Note that irregular verbs can be combined with the same prefixes as described above. The same rules regarding the prefix ge- apply. Therefore the forms for schreiben, verschreiben and aufschreiben are geschrieben, verschrieben and aufgeschrieben respectively.

Which verbs are irregular

A lot of verbs that are irregular in English are irregular in German, too. Unfortunately, this is not always true. It is most likely when the German and the English verb are related (i.e look similar).
Examples:

see:    irregular   sehen:    irregular
buy:    irregular   kaufen:   regular
get:    irregular   bekommen: irregular ;-)

Regular verbs are much more frequent than irregular ones, but a lot of the irregular verbs are used very frequently, for instance haben, sein, gehen, kommen etc.
When in doubt whether a verb is irregular or not, it is best to look it up in a dictionary (See below).

haben or sein as auxiliaries

Whether a verb is irregular or not does not influence the choice of auxiliary.
Most verbs take haben as auxiliary.
A) Verbs which take an accusative object (transitive verbs)
B) Reflexive verbs always take haben as auxiliary.
Examples A:

trinken: Er hat ein Bier getrunken.
lesen:   Sie hat ein Buch gelesen
kochen   Sie haben gestern Spaghetti gekocht.

Examples B

sich freuen   Ich habe mich gefreut
sich kämmen   Er hat sich gekämmt
sich ärgern   Wir haben uns schon lange nicht mehr so geärgert.

The auxiliary sein is taken by verbs that describe

C) the relocation from one place to another or

D) the change of a state

and with

E) sein (be) and bleiben (stay)

Note: none of the verbs from groups C-E is combined with an accusative object.
Examples C: relocation verbs

verb               aux.  irregular  sentence with perfect tense
kommen (come)      sein  yes        Ich bin gekommen.
reisen (travel)    sein  no         Wir sind schon dreimal nach China gereist.
fahren (drive)     sein  yes        Ich bin mit dem Auto nach Kalifornien gefahren.
begegnen (meet)    sein  no         Er ist ihm gestern begegnet.
gehen (go)         sein  yes        Du bist gegangen.
starten (take off) sein  yes        Das Flugzeug ist gestartet.

In southern German (mostly Bavarian) use, also stehen, sitzen und schwimmen are treated like a (non-)movement:

Ich bin gestanden - gesessen - geschwommen. High German is: Ich habe gestanden - gesessen - geschowmmen.
Aber: Ich habe den See durchschwommen.

Examples D: change of state verbs

verb                        aux.   irr.    sentence with perfect tense
aufstehen (get up)          sein   yes     Ich bin heute früh aufgestanden.
einschlafen (fall asleep)   sein   yes     Die Kinder sind endlich eingeschlafen.
verblühen (whither)         sein   no      Die Blumen sind schon verblüht

Examples E: sein and bleiben

Er ist nicht lange geblieben.  He didn't stay long.
Er ist immer nett gewesen.     He has always been nice.

Exeptions to the rules Some of the verbs from group A can be used with an object in accusative case. In this case, they take haben as auxiliary.
Compare:

Ich bin nach Kalifornien gefahren.                  I drove to California.
Ich bin mit dem Auto nach Kalifornien gefahren.     I drove to California by car (literally: with the car)
Ich habe das Auto (Akk.) nach Kalifornien gefahren. I drove the car to California.

The same applies to fliegen (fly), starten and reiten (ride a horse).

sentence structure

The perfect tense consists of two verb forms: an auxiliary and a past participle. Together they form the so called predicate. The predicate consists of all verb parts in one clause.
The sentence structure in perfect behaves as with every two parts predicate (modals plus infinitive, separable verbs etc.)

Main Clauses

In a main clause (Hauptsatz), the conjugated verb (the auxiliary in this case) is in the second position and the past participle stands at the end of the clause.

   First Position (I)       (II)
1) Sein Vater               hat  gestern    ein fantastisches Essen gekocht.
2) Gestern                  hat  sein Vater ein fantastisches Essen gekocht.
   Both: Yesterday, his father cooked a fantastic meal.
3) Ein fantastisches Essen  hat  sein Vater gestern                 gekocht.*
   It was a fantastic meal that his father cooked yesterday.

* The third example is correct, although not very frequent. You might use it if you want to stress what exactly his father has prepared or if you have to repeat the sentence because your partner has not understood this particular part of it.
Second position does not equal second word, as you can see above. However, there is only one group of words allowed before the conjugated verb (the auxiliary in this case). Such groups of words are called “phrases”. While you can put very long phrases in front of the conjugated verb, you must not use two. Therefore the sentence “Gestern sein Vater hat ein fantastisches Essen gekocht” is wrong.

subordinated clauses – Nebensätze

Subordinated clauses begin with a subordinating conjunction. Well known conjunctions of this kind are

weil  dass  wenn.

*In spoken language weil is often used like und or aber, which means that it is followed by a main clause. However, after weil, speakers often pause for a little while. There is no pause after either und or aber.
Weil + main clause is not allowed in written language. Therefore you may say: Ich gehe, weil – (little pause) – ich bin müde. But you wouldn’t use it in a letter. At least not yet.
The correct conjunction for a main clause is denn, which is rarely used in spoken language.
In subordinated clauses the conjugated verb, i.e the auxiliary, stands at the very end of the sentence. The past participle stands directly in front of it. For example:

                  conj.    aux.                 participle  aux.
Ich weiß,         dass  du      das             gemacht     hast.
Ich glaube dir,   weil  du      bisher noch nie gelogen     hast.
Ich glaube dir,   denn  du hast bisher noch nie gelogen.
Ich gehe,         wenn  du                      gegangen    bist.

Usage

Unlike in English the difference in meaning between Perfekt and Präteritum is rather small. The main difference between those two forms lies in usage. Perfekt is mostly used in spoken language, while Präteritum is mostly reserved for written texts. However, the modals, the verbs haben and sein and the expression es gibt are almost exclusively used in Präteritum – even when speaking. One reason might be the frequency of those verbs, the other reason is most likely the very complex perfect forms for modals.
(This is in southern German use; in northern German, you’ll hear the preterite also in spoken language.)
On the other hand, the perfect tense is used in writing too. The more oral the text is, the more perfect tense you will find (for example in personal letters etc.). If an action has happened very recently, it tends to be in perfect tense too.
Look at the following conversation and concentrate on the distribution of Präteritum and Perfekt.
(1) Anna: Hallo Peter. Wo warst du denn? Ich habe dich schon lange nicht mehr gesehen.
(2) Peter: Hallo Anna. Ich war die letzen zwei Wochen im Urlaub.
(3) Anna: So? Wo warst du denn genau?
(4) Peter: Auf der Insel Elba, in einem fantastischen Hotel. Es gab jeden Abend ein Büffet und man konnte essen, so viel man wollte!
(5) Anna (lacht): Ich glaube dir sofort, dass dir das gefallen hat. Du hast aber nicht nur gegessen, oder? Was hast du denn den ganzen Tag gemacht?
(6) Peter (lacht auch): Nein, natürlich nicht. Ich bin viel geschwommen, ich habe mir die Insel angeguckt und am Abend bin ich immer zum Tanzen in eine Disco gegangen.
(7) Anna: Aha… Und? Hast du jemanden kennen gelernt?
(8) Peter (grinst): Kein Kommentar.

Vocablary to help you understand the text:

der Urlaub, -e   vacation
genau            exactly, precisely
die Insel, -n    island
das Büffet, -s   buffet
gefallen         like
angucken         to look at (colloquial)
kennen lernen    get to know
grinsen          grin

Used forms to talk about past events

Präteritum         Perfekt
du warst (1/3)     habe gesehen (1)
ich war (2)        es hat gefallen (5)
es gab (4)         du hast gegessen (5)
konnte (4)         du hast gemacht (5)
wollte (4)         ich bin geschwommen (6)
                   ich habe angeguckt (6)
                   ich bin gegangen (6)
                   du hast kennen gelernt

How to find the forms in a dictionary

Unless you have a special dictionary for learners, not all the forms will be spelled out. Regular forms are often omitted. The same goes for the auxiliary haben. If no forms are indicated, you may assume that the verb is regular and has the verb haben as an auxiliary. However, if you find the abbreviation itr or i. (for intransitive) behind the verb, the auxiliary is often sein. Intransitve verbs don’t have an accusative object and these are often used with sein, while transitive verbs (tr. or t.) are always conjugated with haben.
Sometimes not even the forms of irregular verbs are given in the lexicon entry. Irregular verbs are often indicated by irr. for irregular or a similar abbreviation. In that case, look for a list of irregular verb forms in the index of your dictionary.
To find the past participle of separable verbs you often have to cut the prefix and look for the base form of the verb. If you look for aufstehen (get up), you probably find your answer in the entry of stehen. Remember: The prefix ge goes in between the prefix of the separable verb and the verb itself: auf + ge + standen.
When working online, you might consider using Canoo. Enter an arbitrary form of the word you are interested in into the mask. Hit enter. On the results page, choose the link Flexion behind the appropriate entry (or inflection in the english version). You will get a table of all possible verb forms.

Tips for learning

Irregular forms are just that – irregular. Therefore you have to learn them by heart. By learning four forms, you can construct every verb form for a given verb.
The forms you should know are:

Infinitiv    Präsens          Präteritum    Hilfsverb  + Partizip Perfekt
infinitiv    3rd person       preterite     auxiliary  + past participle
gehen        geht             ging          ist        + gegangen
nehmen       nimmt            nahm          hat        + genommen
fahren       fährt            fuhr          ist        + gefahren
lesen        liest            las           hat        + gelesen
essen        isst             aß            hat        + gegessen
kommen       kommt            kam           ist        + gekommen
bleiben      bleibt           blieb         ist        + geblieben
sein         ist              war           ist        + gewesen
anfangen     fängt ... an     fing ... an   hat        + angefangen
...

All forms – besides the infinitive of course – should be in 3rd-person singular.
A good way to learn those forms is to put them on small cards. On one side you write the infinitive and probably a sentence to illustrate the usage of the verb. On the backside you put the rest of the forms and – if needed – a translation of the verb. When learning, you look at the infinitve and try to remember the forms and the meaning. You can easily verify your hypothesis by flipping the card.
If you encounter a verb you want to learn, look it up in a dictionary. If it is irregular, learn the verb together with its defining forms. Like that, you spare yourself a lot of trouble later on.

Preterite

Forms – Formen

Regular Forms

Regular (or better, weak) verbs take the ending -te. The person endings are added afterwards. Note that the forms for 1st- and 3rd-person singular are the same.

ich lern -te
du  lern -test
er  lern -te
wir lern -ten
ihr lern -tet
sie lern -ten
Sie lern -ten

If the stem of a verb (infinitive minus -en) ends in -t (arbeit-en), -d (end-en) or consonant plus m or n (öffn-en, rechn-en) you add an -e before the preterite endings.

ich arbeit -e -te
du  arbeit -e -test
sie arbeit -e -te
wir arbeit -e -ten
ihr arbeit -e -tet
sie arbeit -e -ten
Sie arbeit -e -ten

Irregular Forms

without -te

The strong verbs belong to this group. The endings are easy to memorize. It is harder to know which vowel to use.

fahren
ich fuhr -
du  fuhr -st
sie fuhr -
wir fuhr -en
ihr fuhr -t
sie fuhr -en
Sie fuhr -en

The rule mentioned above for t/d, double-consonant + n/m applies also for irreglar verbs.

stehen
ich stand -
du  stand -(e)st
er  stand -
wir stand -en
ihr stand -et
sie stand -en
Sie stand -en

gehen, ging, gegangen
stehen, stand, gestanden

with -te

Few irregular verbs take the -te ending. Examples are: nennen, rennen, kennen, bringen, denken and the irregular modals (können, dürfen and müssen).

nennen
ich nann -te
du  nann -test
er  nann -te
wir nann -ten
ihr nann -tet
sie nann -ten
Sie nann -ten

Usage

Unlike in English the difference in meaning between Perfekt and Präteritum is rather small. The main difference between those two formes lies in usage. Präteritum ist mostly used in written language, while Perfekt is mostly used in spoken language and in texts that have an oral touch like personal letters. However, the modals, the verbs haben and sein and the expression es gibt are almost exclusively used in Präteritum – even when speaking.

How to find the forms in a dictionary

Unless you have a special dictionary for learners not all the forms will be spelled out. Regular forms are often omitted. Irregular verbs are often marked by irr. for irregular or a similar abbreviation. In that case, look for a list of irregular verb forms in the index of your dictionary.
When working online, you might consider using Canoo. Enter an arbitrary form of the word you are interested in into the mask. Hit enter. On the results page, choose the link Flexion behind the appropriate entry (or inflection in the English version). You will get a table of all possible verb forms.

Tips for learning

Irregular forms are just that – irregular. Therefore you have to learn them by heart. By learning four forms, you can construct every verbform for a given verb.
The forms you should know are:

Infinitiv    Präsens          Präteritum    Hilfsverb  + Partizip Perfekt
infinitiv    3rd person       preterite     auxiliary  + past participle
gehen        geht             ging          ist        + gegangen
nehmen       nimmt            nahm          hat        + genommen
fahren       fährt            fuhr          ist        + gefahren
lesen        liest            las           hat        + gelesen
...

All forms – besides the infinitiv of course – should be in 3rd-person singular.
A good way to learn those forms is to put them on small cards. On one side you write the infinitive and probably a sentence to illustrate the usage of the verb. On the backside you put the rest of the forms and – if needed – a translation of the verb. When learning, you look at the infinitve and try to remember the forms and the meaning. You can easily verify your hypothesis by flipping the card.
If you encounter a verb you want to learn, look it up in a dictionary. If it is irregular, learn the verb together with its defining forms. Like that, you spare yourself a lot of trouble later on.

Future Tense

Talking about future with the present tense

German uses the Present Tense to talk about the future whenever it is clear to both speaker and listener that the future is meant. In the dialogue example:

Wenn du zu Hause bleibst, kommen wir dich besuchen.
If you stay at home, we shall come and visit you.

The whole conversation is about the future, so there is no need to indicate it again in the tense of the verb.
Some more examples:

Ich schreibe den Brief heute Abend.
I will write the letter this evening.
Wir gehen nächstes Jahr nach Spanien.
We will go to Spain next year.

Future Tense

Futur I

Where the meaning would not otherwise be clear, and in more formal language, e.g. to express an intention, German talks about the future tense by using werden plus the infinitive at the end of the clause. The forms of werden are:

ich werde
du wirst
er/sie/es/man wird
wir werden
ihr werdet
sie/Sie werden

Examples:

Ich werde ein Haus bauen.
I shall build a house. (an intention)
Wir werden sehen.
We will see.

The future can also express some inescapable fate:

Sie werden alle umkommen.
They will all perish.

Future II

If the sentence is speculative, “sein” or “haben” is added to the verb and Futur II is formed:

Sie werden angekommen sein.
literally "they will have arrived" - meaning "(I gather) they have arrived (by now)"

Sie werden es gemacht haben.
"they will have done it"

Normally, you use Futur II when speaking about something that should have happened already, but you are not sure or you can’t prove it.