Question

What _________ at 8 last night?
A) Did you do
B) You did
C) Were you doing
D) Are you doing

Answer 1

Hint: The sentence suggests that an action was taking place at some point in the past. The action taking place in the past was continuous. So the required verb should also be in the past continuous tense.

Complete answer:
A verb is a word that describes an event, activity, or situation. In a sentence, it is the grammatical centre of the predicate.

Let us look at the given options:
Option A) This option is incorrect because ‘Did’ is the past tense form of do whereas we have to use past continuous tense.
Option B) In this sentence, the verb must come before the subject, not the subject before the verb. Therefore, “you did” is incorrect.
 Option C) were you doing- is correct. This option is correct because it denotes an action that took place in the past in a continuous manner. ‘Doing’ is the continuous tense of the verb ‘do’ and it is written with the past tense of the auxiliary verb i.e., were. Did you do is the past tense form of the verb ‘to do’ It is not used to denote a continuous action that happened in the past.
Option C) This option is incorrect because Are is used to denote an action that is taking place in the present. This is opposite to the sentence as the sentence suggests an action that took place in the past.

Thus, the correct answer is Option C) were you doing.

Note: Auxiliary verbs give functional or grammatical meaning to the phrase in which they appear, such as tense, aspect, modality, voice, stress, and so on. Auxiliary verbs are generally found next to an infinitive verb or a participle, which give the clause's major semantic meaning.