—Do you know the girl with our English teacher often?— Yes her name is Helen. A. whom to

问题补充：

—Do you know the girl with our English teacher often?

— Yes, her name is Helen.

A. whom to talk

B. who talks

C. who is talking

D. whom talks

答案：

A. whom to talk

(答案→)B. who talks

C. who is talking

D. whom talks

解析：句意：你认识这个经常和我们的英语老师谈话的女孩吗？——是的，她的名字叫海伦。结合语境可知上文中先行词the girl为定语从句的逻辑主语，故引导词用who。根据时间状语可知定语从句中描述的是经常性的动作，故用一般现在时态。故选B。