Who is the person 　is standing at the school gate ?A. whoB. thatC. whichD. whom

问题补充：

Who is the person is standing at the school gate ?

A. who

B. that

C. which

D. whom

答案：

A. who

(答案→)B. that

C. which

D. whom

解析：考察定语从句。本题定语从句的先行词是the person，后面定语从句中缺主语，而且先行词是人，可以使用that/who都可以。因为本句前面已经有了who，为了避免重复，所以本句使用that引导定语从句。句意：站在校门口的那个人是谁？故B正确。