you needn't worry about your son.(意思相同) you don't ___ _____worry about your son.
问题描述:
you needn't worry about your son.(意思相同) you don't ___ _____worry about your son.
答
need to
needn't do sth(need是情态动词)=don't need to do sth(need是实意动词)
答
need to