Question

My mother _________ cook on Sundays

Answer 1

My mother used to cook on Sundays

• When we look at the sentence structure above, we realize that the sentence depicts an event that used to occur in the past.
• We cannot use present tense 'is used to' to depict an action from the past.
• Hence, the past form of the verb 'used to' is the correct option to fill in the blank.

The question is not complete. The complete question is:

My mother _________ cook on Sundays.

used to

is used to