The boy looked at the stranger carefully， ________who he would be．

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Our teacher received a letter ________him to attend a lecture．

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They looked forward with hope ________a chance to receive further education．

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Look！How busy the building workers are！

Yes，I see． The houses ________by them will be completed next week．

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They don't allow ________in the meeting room．

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（1）Their research work has ________a new stage．

（2）A foreign language cannot be learned rapidly；it must be learned

（3）They were walking ________．

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（1）The ________adult mosquitoes emerge from the pupae．

（2）I could see the plane's ________out of the window．

（3）If he ________the election，I will leave the company．

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There is no theme park in our city．But don't worry．A new one ________soon．

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There are ________of animals in Wuhan Animal Park．

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We have a pencil ________the paper．You can use them．

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