any other use for the word IF?

来源：百度知道 编辑：UC知道 时间：2024/05/08 17:33:01
And if, with the decay of vitality, weariness increases, the thought of rest will be not unwelcome.

Who can tell me what the word if in the sentence means???
thanks alot!

就是普通的连词用法啊!
引导条件/时间状语从句if weariness increases,"如果/当疲倦感增加"(那么就会希望休息)
with the decay of vitality是插入的状语"随着青春活力的消失"

with the decay of vitality可以不用看,作插入语,IF表示假设