When he was young, he used to spend his ______ time collecting s

When he was young, he used to spend his ______ time collecting stamps.
A、smart
B、special
C、solid
D、spare
【正确答案】：D
【题目解析】：本题考查词义辨析。smart“聪明的”；special“特别的”；solid“固体的，结实的”；spare“空闲的”。spare time：空闲时间，业余时间。其它选项与time 搭配意思均不正确。