1.(2019· 天津高考，3)A study shows the students who are engaged in after－school activities are happier than ________ who are not.
答案：those 本空指代前面的复数名词the students，同时为后面who引导的定语从句的先行词，此时应该用表示特指的指示代词those。
2．(2018·全国卷Ⅰ，70)If you are time poor, you need run for only half the time to get the same benefits as other sports, so perhaps we should all give ________ a try.
答案：it give it a try “试一试”，相当于have a try。
3．(2018·全国卷Ⅲ，68)When the gorillas and I frightened each other, I was just glad to find ________ (they) alive.
答案：them 此处作find的宾语，用they的宾格形式them。
4．(2017·浙江高考，64)Another nice thing is that you learn both new words and ________ (they) use unconsciously.
答案：their 此处应用形容词性物主代词修饰名词use，指这些词的用法，故填their。
