1.I don't like them and Bob does't like them,either.（改为同义句）
Neither I nor Bob likes them.
2.Peter thinks the new dictionary is too expensive.（改为否定句）
Peter doesn't think the new dictionary is too expensive.
3.The pen is 8 yuan .（对划线部分提问）
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How much is the pen?
4.Mr.yang became a teacher when he was 21.（改为同义句）
Mr.yang became a teacher at the age of 21.
5.The man gave the money to the shopkeeper for the cake.（改为同义句）
The man paied for the cake.
6.My father got up early this morning.he could catch the first train.（合并成一个句子）
My father got up early this morning so that he could catch the first train.