It is a difficult problem for high school students they can properly use the Internet．
| A．what | B．where | C．when | D．whether |
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Can you imagine what problem may ________ when human beings are cloned?
| A．raise | B．cause | C．arise | D．lead |
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— I have learned that it is not easy to get on well with the new boss.
—______? I think that I only need to do my own job well.
| A．So what | B．what for | C．what if | D．how come |
.
— I ‘ll ask our physics teacher to explain Newton’s Second Law of Motion, which she taught us yesterday.
— That’s just _______ most of the students haven’t understood.
| A．what | B．why | C．how | D．where |
.
It didn’t _____ him that she would refuse his invitation
| A．happen to | B．adjust to | C．belong to | D．occur to |
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Your luggage will be ___ by the lorry from the airport to your hotel.
| A．brought | B．conveyed | C．transmitted | D．fetched |