没有区别。bit是bite的过去式，动词为咬的意思。bite 名词为咬伤，动词为咬。例：She was bitten by the family dog.(她被家里的狗咬伤了)

bite：v.咬;叮;蜇;咬饵;上钩；n.咬;(咬下的)一口;小量食物;简单的一餐

相关介绍

例句：

Wind forward to the bit where they discover the body.

往前绕片，绕到他们发现尸体的那一截。

Can you turn the volume up a little bit?

你能把音量开大点儿吗？

Actually, I'll be a bit late home.

说真的，我回家会晚一点。

We can finish this job on time if everyone does their bit.

要是每个人都尽职，我们就能按时完成这项工作。