After several days of social activities, I decided to on my research on the huma

After several days of social activities, I decided to _______ on my research on the human behaviors．

fix

settle

set

concentrate

试题答案

答案：D

句意为：“在几天的社会活动之后，我决定把我的注意力集中到对人类表现的研究上来。”concentrate on…“集中于……”。