As in English, German verbs are modified depending on the person and number of the subject of a sentence, as well as depending on the tense and mood.
The basic form of a German verb is the infinitive. All German infinitives end in either -en or -n .
German has six tenses: present (Präsens), present perfect (Perfekt), simple past (Präteritum), past perfect (Plusquamperfekt), future (Futur I) and future perfect (Futur II).
The present tense also called the simple present (Präsens) is used to talk about the present and future in German.
We can translate it into one of three English tenses: the simple present, present progressive and future with will or going to.
It is the most commonly used tense in the German language.
The perfect tense, also called present perfect (Perfekt), is a past tense.
We use it to speak about actions completed in the recent past.
In spoken German, the present perfect tense is often used instead of the past tense.
Perfekt is mostly formed from the appropriate present tense form of 'to have' (haben) and a past participle of the relevant verb placed at the end of the clause. Some intransitive verbs involving motion or change take 'to be' (sein) instead of haben; this may depend on the exact meaning of the sentence.
Simple past or imperfect (Präteritum), is used to express facts and actions that started and ended in the past.
The past perfect or pluperfect (Plusquamperfekt) expresses actions that took place before a certain point in the past. It is the German equivalent of the English past perfect tense.
The future tense (Futur I) is mostly used to express assumptions about the present or future in German. It is formed from the appropriate present tense form of the verb werden (to become) and, as in English, the infinitive of the relevant verb.
The future perfect (Futur II) expresses the assumption that an action will have been completed by the time of speaking, or by a particular point in the future. To conjugate verbs in the future perfect tense, we need the finite form of werden, the past participle of the relevant verb, and the auxiliary verbs sein/haben.
The imperative mood - das Imperativ is a mood that is used for expressing commands and also polite requests.
There are two different ways to form the Conditional Mood (Konjunctiv II & I) in German. There is a fully conjugated form or Simple Conditional, and there is also a Compound Conditional form that uses werden as a helper verb. When to use the German Conditional:
In German, prepositions and modifying prefixes are frequently attached to verbs to alter their meaning. Verbs so formed are divided into separable verbs which detach the prefix under certain circumstances and inseparable verbs which do not. The conjugations are identical to that of the root verb, and the position of the prefix for both separable and inseparable verbs follows a standard pattern. The prefix's effect on the verb is highly unpredictable, so normally the meaning of each new verb has to be learned separately.
Separable verbs (Trennbare Verben) detach their prefixes in the present, imperfect and imperative. The prefix is placed at the end of the clause. The past participle is the prefix attached to the normal past participle. The infinitive keeps the prefix where it is used, for example in the conditional and future tenses.
Inseparable verbs (Untrennbare Verben) retain the prefix at all times. The past participle has the prefix in place of ge- but keeps any irregularities of the root verb's past participle.
A number of verbs are separable with one meaning and inseparable with another. For example, übersetzen means 'to translate' as an inseparable verb but 'to ferry' as a separable verb.
In both English and German, infinitive clauses are a kind of dependent clause in which there is no grammatical subject, only an implied one, and therefore the verb is not inflected. An infinitive clause is particularly dependent on the main clause of the sentence for its meaning. The infinitive, which is combined with "zu" goes to the end of the clause:
If the verb in question has a separable prefix, the zu goes between the prefix and the stem (e.g. anzufangen - 'to begin', zuzumachen - 'to close').
It can be useful to view infinitive clauses as being transformed from main clauses. To make the transition, one drops the subject and converts the finite verb to an infinitive, which goes to the end of the clause.
German uses um ... zu in order to express intention. This construction can usually be translated by "in order to":