Question

( ) 1. ―Does Mr. Li know the lady      in the hall?

      —Yes, he does.
A. who is    B. who are

C. whom is    D. which is

Answer 1

1. A在定语从句中，谓语动词必须与先行词保持人称和数的一致，而且先行词指代人在从句中作主语，应使用who/that,且不能省略。