根据所给中文完成句子（共5小题；每空0.5分，满分5分）
你应该把注意力集中在学习上。
You should __________ your attention            your study.
杰克正从手术中恢复过来，不久将回家。
Jack is _________            his operation and he will soon go back home.
这种药物的副作用是容易形成习惯
One of the _________          of this drug is the easiness of habit-forming.
他们正在加紧搜索一种像人一样的动物。
They are                       their research for a man-like creature.
昨天你为什么没有出现在会议上？
Why didn’t you                     at the meeting yesterday?