问题

.Getting to other planets or to the moon _____ many problems

A:involve
B:involves
C:involving
D:to involve

正确答案是：

同类题型

从句式特征来看，不同的一项是（）

I hear the birds _______.

___ online games for two years, but I’ve neverregretted giving it up.

The Russian Railway has _______ the prices of tickets for long-distance trains.

I’m so glad to see you back，Lucy. How long　　　　at your grandma’s？