These trees were planted last year.变成否定句They weren't planted last_英语解答

These trees were planted last year.变成否定句They weren't planted last year.为什么these trees 要用they

人气：233 ℃　时间：2019-08-21 22:12:05

解答

these trees 改成they是因为上下文为了避免重复用相同的词these trees而用they的,而单纯从一个句子改成否定句是不用改成they的.