I _______ have been more than six years old when the accident happened．
| A．shouldn’t | B．couldn’t | C．mustn’t | D．needn’t |
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–Did you see ____ English teacher?
--I saw him at ____ work in the office just now.
| A．an, / | B．the, a | C．the, / | D．the, the |
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When ____ a new word, you’d better _____ a dictionary.
| A．come across, refer to | B．coming across, consult |
| C．coming across, look up | D．come across, look through |
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After the quarrel, I tried all my best to fix the misunderstanding between us, but all my efforts seemed ______.
| A．in trouble | B．in case | C．in time | D．in vain |
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-- Better get down to your work, Jack.
--- _____________.
| A．It’s my pleasure | B．Not to mention it |
| C．Mind your own business | D．You’re welcome |
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If you use another method to solve this problem, you’ll probably ______ it.
| A．make | B．get | C．finish | D．take |