问题补充：
Occasions are quite rareI have the time to spend a day with my kids.
A. who
B. which
C. why
D. when
答案：
A. who
B. which
C. why
(答案→)D. when
解析：句意：在一天的时间里我很少有机会和我的孩子待在一起。本题是when引导的从句作Occasions的同位语。整个句子调整一下顺序：Occasions when I have the time to spend a day with my kids are quite rare.这样就容易理解了。
此题考查when引导同位语从句的用法。
