Mary also wanted to buy some picture books and color pencils.这里的buy怎么不用过去式啊?

Mary also wanted to buy some picture books and color pencils.这里的buy怎么不用过去式啊?
Mary also wanted to buy some picture books and color pencils.这里的buy怎么不用过去式啊?

Mary also wanted to buy some picture books and color pencils.这里的buy怎么不用过去式啊?
因为前面有to,是动词不定式了,必须要用动词的原型.
这个句子的过去式已经在谓语动词want上体现了.

want to do sth 是固定短语 用动词原形