问题

The robot needs ________ once a month. And we will check it for you for free.
A:to check
B:be checked
C:checking
D:Check;
B:be checked
C:checking
D:Check;
正确答案是:
同类题型
It’s common sense that in summer people like to seek shade the air is cooler.
What a table! I’ve never seen such a thing before. It is____it is long.[ ]
The students are passing the ball from one to ______ .
What _____ Yu Ping usually _____ in her free time—She usually goes to the library.
What will you do if no news _____ from your sister tomorrow?— I will go to her house myself. [ ]