Question

There are some health problems that, when       in time, can become bigger ones later on.

A．not treated	B．not being treated
C．not to be treated	D．not having been treated

Answer 1

A

试题分析：考查状语从句的省略：句意为：有些健康问题，如果不及时处理，以后会变得更严重。when not treated in time 为插入语，在本句中为时间状语从句，把that can become bigger ones later on 这个定语从句给隔开了。when 引导时间状语从句时，可以出现省略的现象，但必须满足两个条件：首先，时间状语从句中的主语必须和主句主语一致；其次，从句中含有be 动词。本句中补充完整的状语从句为：when they are not treated in time，其它选项形式不对。故答案为A 项。