is的过去式和过去否定式:was ,wasn't
are的过去式和过去否定式:were,weren't
wasn't是is的过去否定形式啊,如果还有其他疑问,欢迎提问,希望能帮到你
英语中is和are过去式的写法和运用
is 过去式是 was, are 的过去式是were.
1,This letter is wet now. This letter was dry .
2,My shoes are clean now. My shoes were dirty.
3. His room is clean and tidy now. His roon was mass .
4,The weather is warm . The weather was so cold.