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.