--What makes her so worried?

--______ at school.

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A．Because her son doesn't work hard

B．Because of her son's not working hard

C．Her son doesn't work hard

D．Her son's not working hard

--How are you today?

--Oh, I ______ as ill as I do now for a very long time.

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When we ______ after a long talk, we found the children sleeping in ______ beds.

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A cook will be immediately fired if he is found ________ in the kitchen.

[　　]

The books we looked forward to _________ yesterday.

[　　]

The flu is believed __________ by viruses that like to reproduce in the cells inside human nose and throat.

[　　]

I've won a holiday for two days to Florida. I _______ my mother.

[　　]

Next year my little sister _________ ten years old.

[　　]

I ________ ping-pong quite well, but I haven't had time to play since the new year.

[　　]

I'm sure he will help her if she _______ him.

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