1. 用于本义，意为“与……一样远”“一直到……” (在否定句中也可用 so far as)。如：

We walked as far as the river. 我们一直走到河边。

We didn’t go as [so] far as the others. 我们走得不如其他人远。

I’ve read as far as the third chapter. 我已读到第三章。

2. 用于引申义，意为“就……而言”“从……来看”“尽……所能”“只要”(有时可用 so far as)。如：

We’ll help you as far as is possible. 我们会尽可能帮你。

As [So] far as I know, that is highly unlikely. 就我所知，那是极不可能的。

As [So] far as I can see, there are no mistakes. 据我看 没有什么差错。