Auxiliaries
To know the uses of the auxilar, you need to know the different auxilaries.
1. some auxiliaries are used to build questions in the present and past like do, does and did.
Ex: Do you like coffee?
aux + s + verb + obj
I do not play video games.
s + aux + not + verb + obj.
2. some auxiliaries are used to make compound tenses, such as: present progressive, past progressive, present perfect with these auxliliaries: am, is, are, eas, were, have, has, had...
Ex: I am playing now. ( present progressive)
she has eaten that since she was 5. ( present perfect) the aux: has, main verb: eaten from eat.
we were cooking at 6 pm. ( past progressive) the aux: were, main verb: cooking from cook.
They had finished. ( past perfect) aux: had, main verb: finished from finish.
Modal
The modal verbs are used not only in the affirmative, negative and interrogative but also they change the meaning sometimes.
If i take tthese two examples about the modal CAN.
Ex: i can play soccer. (it means ability)
It can be raining tonight. (it means possibility)
