They didn't called their friends.这句话中有一处是错误,请你帮我找出来并说明为什么要改成这个单词

问题描述:

They didn't called their friends.这句话中有一处是错误,请你帮我找出来
并说明为什么要改成这个单词

Called 改成 call

called---call

They didn't call their friends.
助动词did后面要用原形