There seems to be two causes as I try to figure out __________ that prevents so

题干

There seems to be two causes as I try to figure out __________ that prevents so many children from being as happy as before.

A．how it is	B．when it is
C．what it is	D．why it is

上一题下一题 0.64难度单项选择更新时间:2014-12-15 03:32:22

小学学科试题库

初中学科试题库

高中学科试题库