We will do what we can ________ help them practice ______ English.
A:/, to learn
B:to, to learn
C:to, learning
D:/, learning
我们总是在东方迎来黎明的曙光,西方送走黄昏的落日,是因为( )
____ Ben row a boat last Sunday?
指出下列各句中,“为”字的意义和用法不同的一项是( )。