My classmates often help me do my himework.

问题描述:

My classmates often help me do my himework.
为什么要加s

意思为:同学经常帮助我做作业.这里没说明是一个同学,所以用的复数,与后面的谓语动词help一致.如果用classmate的话,动词则应该用单数helps.(himework应该打错了吧,是homework)