“Tom wasn't watch TV last night.”是否有错？

有啊
wasn't是be动词，不能直接加动词原形啊
用didn't

有错。
可以改成：Tom didn't watch TV last night.
或者Tom wasn't watching TV last night.
一种表示一般过去时，另一种表示过去进行时。

Tom didn't watch TV last night

有错。
可以改成：Tom didn't watch TV last night.
或者Tom wasn't watching TV last night.
一种表示一般过去时，另一种表示过去进行时。

这是要看具体情况的 。

应该是Tom didn't watch TV last night.

有~~应该改为Tom didn't watch TV last night