1(after a noun N and before a predicate P) the reason why N P
2Example: 我之所以討厭他|我之所以讨厌他[wo3 zhi1 suo3 yi3 tao3 yan4 ta1] "the reason why I dislike him (is ...)"
Example
tā men他们zhī suǒ yǐ之所以méi yǒu没有yóu yǒng游泳，jìu就yīn wèi因为tiān qì天气hěn很lěng冷。
他们之所以没有游泳，就因为天气很冷。
They didn't swim because it was cold.