Use of 花/用/要 to express how long one took to accomplish an action

[MengJiaSheng]

I would be really thankful if someone could explain the use of these three words. I am quite sure about how to use 要 to indicate how long a certain action takes:

我从我家里到市中心要二十分钟。

However I am not clear how this pattern would change if one speaks about a past event....I think you would use 花/用?

我昨天做作业 花/用 两个小时了。

Would that be correct or how exactly do you indicate how long an action took in the past?

谢谢你们

[Hofmann]

I would put 了 after 花 or 用.

[glock]

how exactly do you indicate how long an action took in the past?

I'd say 我昨天做了 两个小时的作业了。

However I think these are ok;

昨天花两个小时做作业了。

昨天做作业花了两个小时了。

Also If I use "离合动词“ I say ” 睡几个小时的觉“

written by a non-native speaker!

[jiangping]

要 means "takes (a certain amount of time)". So you can't use it for actions like doing homework, but it's fine for sentences like "it takes 20 minutes on the bus", etc.

If you want to say you did an action for a certain amount of time, you don't need to change the verb, just use the usual one. The structure is:

subject - verb - duration 的 object

so, 我昨天做了兩個小時的作業。I did homework for 2 hours yesterday.

If you want it to be in the "past", the 了 goes after the verb, rather than at the end of the sentence. You could put one at the end of the sentence as well if it was in certain contexts, but that's something completely different.

For the future, you could drop the 了 and add a 要 (here a modal verb, not like "takes..." above), so it would be:

我明天要做兩個小時的作業。I am going to do homework for 2 hours tomorrow.

花 is used in the sense of "spending (time)": 花時間

So you could say something like 我把所有的時間都花在中文的學習上. I spend all my time studying Chinese.

I'm not too sure about 用. I can't think of anywhere where it'd be used specifically for time, unless it just happened to be the normal verb for an action, like 你要用多久？How long are you gonna use (it) for? I'm not a native speaker though, so maybe it can be.

To sum up:

要 to take (a certain amount of time)

花 to spend (a certain amount of time)

and if it's just a normal statement about doing an activity for a certain amount of time, then there's no need to change the verb at all. You just put the duration (兩個小時，三天，etc) after the verb.

Hope this helps!

Edited February 8, 2009 at 02:52 AM by jiangping

[MengJiaSheng]

Thanks a lot, your answers really helped me!

Edited February 15, 2009 at 12:19 PM by MengJiaSheng