取得操作证的特种作业人员必须定期进行复审,根据复审根据条件不同有()。
A. 2年一次
B. 3年一次
C. 4年一次
D. 5年一次
Which of the following sentence is grammatically incorrect?
A. She did nothing but wait.
B. She did nothing but to wait.
C. There’s no choice for her but to wait.
Which one of the following is more natural, the active form or the passive form?
A. I have a lot of work to do
B. I have a lot of work to be done.
C. I have a lot of work to do/to be done.
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