Scientists have reached the conclusion ________ the temperature on the earth is getting higher and higher.

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________ this material can be used in our factory has not been studied yet.

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________ still needs to be discussed.

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A．How is the plan to be carried out

B．How the plan is to be carried out

C．Why is the plan carried out

D．Why the plan carried out

________ a pity you missed the lecture made by Professor Qian.

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________ will take part in the physics contest will be announced at tomorrow's meeting.

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He is satisfied with ________ his son has achieved．

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I met her ________ in a crowded bus．

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It ________ that space is limitless．

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On his way home, he found a wallet ________ on the ground．

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I'll help you, ________ I don't sleep for a night．

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