1.(2019·全国卷Ⅰ，63)Modern methods ________ tracking polar bear populations have been employed only since the mid－1980s.
答案：of/for a method of/for doing sth. “做某事的方法”。
2．(2019·全国卷Ⅲ，63)We were first greeted with the barking by a pack ________ dogs, seven to be exact.
答案：of a pack of是固定搭配，意为“一群……”。
3．(2019·浙江高考，61)The answer ________ this question is not clear.
答案：to the answer to ... “……的答案”。
4．(2018·北京高考，14)—Good morning, Mr Lee's office.
—Good morning. I'd like to make an appointment ________ next Wednesday afternoon.
答案：for make an appointment for “……时间的预约”。
