Question

【题目】My parents ________teachers. They teach in the same school.
A.are all
B.all are
C.are both
D.both are

Answer 1

【答案】C
【解析】句意：我父母都是老师，他们在同一所学校教书。both两者都；all（三者以上）都；both、all通常位于系动词后行为动词前。故选C。