用方框里所给词或词组的适当形式填空。

1．The clever Chinese invented the abacus in the __________ century.

2．It’s __________. He has got more than me.

3．She often __________ her friend’s house on her way home.

4．He is quiet at home but behaves __________ at school.

5．Be careful. The two__________ on the table cut well.