问题
选择题
The first thing _____ my brother is 
going to do this afternoon is to write a letter.
A．which
B．that
C．why
D．who
答案
答案：B
本题考查定语从句that的用法。在定语从句中先行词为当先行词是不定代词all, much, something, everything, anything, nothing, none, the one, thing时，不定代词用that. 在定语从句中当先行词为物时，用which或that; C项为副词，在定语从句充当状语，与题意不符，故排除。D项当先行词为人时，用who或whom. 故选B。