as long as引導(dǎo)的是條件狀語(yǔ)從句，意思是“只要”，所以，狀語(yǔ)從句能用的時(shí)態(tài)都可以用，除了不能用一般將來(lái)時(shí)。因?yàn)樵跅l件狀語(yǔ)從句中，需要用一般現(xiàn)在時(shí)取代一般將來(lái)時(shí)。
1.表示條件，意思是“只要”。如:
As long as you tell the truth，I’ll try to help you.
只要你告訴我實(shí)情，我會(huì)盡力幫助你。
You may take this book away so long as you return it on time.
只要你按時(shí)歸還，就可以把這本書(shū)拿走。
2.表示原因，意思是“既然，由于，因?yàn)?rdquo;。如：
1. As long as we've driven this far, we might as well go on.
我們既然已經(jīng)駛得這么遠(yuǎn)了，就不妨繼續(xù)前進(jìn)。
2. As long as you are going, I'll go too.
既然你要去，那么我也去。
3.As long as the weather is changeable these days,we’d better get in wheat in time.
由于這幾天氣候變化無(wú)常，我們最好及時(shí)把麥?zhǔn)崭钔辍?/p>
1.as long as 和 so long as 均可表示“只要”，用于引導(dǎo)條件狀語(yǔ)從句，兩者沒(méi)什么區(qū)別。如：
I don't care so/as long as she lets me be with her son.
只要她讓我和她兒子在一起，我不在乎。
You can take my car as/so long as you drive carefully.
你可以用我的汽車，只要你小心點(diǎn)兒開(kāi)。
You may use my dictionary as/so long as you don't keep it too long.
只要使用時(shí)間不太長(zhǎng)，你可以用我的詞典。
2.當(dāng) as long as 用于本義表示“與……一樣長(zhǎng)”時(shí)，與 so long as 在用法上是有區(qū)別的，即 as long as 可用于肯定句或否定句，而 so long as 只用于否定句，不用于肯定句。如：
It took three times as long as I had expected.
這件事比我預(yù)料的多花了兩倍的時(shí)間。
