The boy is so young that he can't look after himself.We have worked here[since,as]I left school.
问题描述：
The boy is so young that he can't look after himself.We have worked here[since,as]I left school.
第一句变同义句两种；1,The boy isn't--- --- ---look after himself.2,The boy is--- --- ---look after himself.
答
old enough to
too young to
选since