as long as引导的是条件状语从句，意思是“只要”，所以，状语从句能用的时态都可以用，除了不能用一般将来时。因为在条件状语从句中，需要用一般现在时取代一般将来时。
1.表示条件，意思是“只要”。如:
As long as you tell the truth，I’ll try to help you.
只要你告诉我实情，我会尽力帮助你。
You may take this book away so long as you return it on time.
只要你按时归还，就可以把这本书拿走。
2.表示原因，意思是“既然，由于，因为”。如：
1. As long as we've driven this far, we might as well go on.
我们既然已经驶得这么远了，就不妨继续前进。
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.
由于这几天气候变化无常，我们最好及时把麦收割完。
1.as long as 和 so long as 均可表示“只要”，用于引导条件状语从句，两者没什么区别。如：
I don't care so/as long as she lets me be with her son.
只要她让我和她儿子在一起，我不在乎。
You can take my car as/so long as you drive carefully.
你可以用我的汽车，只要你小心点儿开。
You may use my dictionary as/so long as you don't keep it too long.
只要使用时间不太长，你可以用我的词典。
2.当 as long as 用于本义表示“与……一样长”时，与 so long as 在用法上是有区别的，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.
这件事比我预料的多花了两倍的时间。
