1.belonged to 属于

例句:He deduced that the two children belonged to the couple.

他推断这俩小孩是这对夫妇的。

2.On balance 总的来说

例句:On balance, the book is a friendly, down-to-earth introduction to physics.

总而言之，这是一本通俗而务实的物理入门书。

3.In fact 事实上

例句:In fact, those people have been promoted.

事实上，那些人已经升职了。

4.the opposite sex 异性

例句:We find members of the opposite sex more attractive when under the influence.

我们喝醉时感到异性更具吸引力。