问题补充:
Don’t let the child who is go to school.
A. so young as to
B. not old enough to
C. not old enough
D. too young to
答案:
A. so young as to
B. not old enough to
(答案→)C. not old enough
D. too young to
解析:这题考查定语从句:who is old enough是定语从句,修饰the child,而谓语let后面接宾语+省略to的不定式。选C。句意是:别让年龄不够的孩子上学。