I. Theory
Modal verbs are a category of verbs that are used to indicate or describe the subject’s stance on the sentence’s main verb. Although modal verbs can function on their own at times, they are almost always found in a sentence with another verb. Here, we see examples of modals in English: 
I want to go to the movies. You should work tomorrow. May I speak with you? In German, we find that modal verbs are used in a similar way in terms of meaning and construction.
-  In German, the second verb remains in its infinitive form when used with a modal verb:
 
 | Ich möchte Deutsch sprechen. I would like to speak German.
 
 Darf ich hier rauchen?
 May I smoke here?
 
 Willst du etwas essen.
 Do you want to eat something?
 
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