Modal Auxiliaries

Look at the following sentences:

• Ich will in Mannheim studieren.
• Ich darf meinen Freund besuchen.

The highlighted verbs are modal auxiliaries. They do not express an action performed by the subject, they rather express a mode which may enable, allow, motivate, force, or oblige the subject to do what the main verb expresses.

The verb that expresses the action is in the infinitive: studieren, besuchen.

In English, the most common modals are can, must, want to, may, ought, should. Most of them have equivalents in German. In this chapter we will introduce:

• können = can
• wollen = want to
• müssen = must
• dürfen = to be allowed to
• sollen = to be to, to be supposed to

Some of these verbs you have already encountered in our dialogues. They are, in fact, very frequently used - and they are irregular. There is one more modal, mögen, which adds the sense of "would like to", but it is almost never used in the perfect or present tenses; you will see it, and want to use it, as möchten (the subjunctive, which adds that sense of "would").

As with the auxiliaries sein and haben, you need to learn: the infinitive, the past participle, and the present and perfect tenses, and also the simple past. The most irregular verbs are always the ones that are used the most!

The Modal Perfect Tense

The infinitives and past participles of these modal auxiliaries go like this:

Notice that the umlaut vowels in the infinitive have no umlaut in the past participle.

All modals use 'haben' as auxiliary to form the perfect - BUT - they don't usually use these past participles! When the modal is being used as an auxiliary with another verb in the infinitive, the perfect is formed by 'haben' plus the infinitive instead:

Let us see how to replace the present tense of the modal by the perfect in our two model modal sentences:

• Ich will in Mannheim studieren.
• Ich darf meinen Freund besuchen.

Instead of:

• *Ich habe in Mannheim studieren gewollt. (wrong)
• *Ich habe meinen Freund besuchen gedurft. (wrong)

Germans simplify things by tacking the infinitive of the modal at the end of the sentence, after the infinitive of the main verb. So, what do you get?

• Ich habe in Mannheim studieren wollen.
• Ich habe meinen Freund besuchen dürfen.

But you can avoid all this by using the simple past tense of the modal.

• Ich wollte in Mannheim studieren.
• Ich durfte meinen Freund besuchen.

Now you can see why you will want to learn the past as well as the present tense!