focus on doing还是do（spend in doing还是on doing）

focus on用 doing而不能用do.中文意思是“集中/聚焦于……做某事”。

例如，课堂上，我们应该集中精力认真听讲。We should focus on listening to the teachers carefully in class .

再如，现在你应该把重心放在调整心态上。Now you should focus on adjusting your mood and attitude.