【题目】选词填空。
【1】—Who________(is/ are) you?
—I ________(am/ is) Mary.
【2】Where ________your friends going? (is/ am/ are )
They ________ going to the zoo.
【3】Her cousins ________ (visit/ visits) Tianjin every year.
【4】He goes to school ________ (in/ on) time.