
Somehow, I managed to teach ESL for over 10 years before I learned what this is. The expression “is supposed to” is called a semi-auxiliary verb. In the sentence in the title, “study” is the main verb.
The expressions below are all called semi-auxiliary verbs. They are followed by the main verb.
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(have) to
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(be) supposed to
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(be) able to
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(be) going to


