簡單英語問題,請指教!!!!!

Above answers are good & in details. I just want to say: I want to sleep is correct but not a complete sentence.
English speaking people would never say like that, such as:
I ate dinner, I look movie, I want to sleep.... etc., you should say:
I had my dinner at home.
I watched the movie with my brother John.
I want to get some sleep. or: I am very sleepy

It is perfectly fine with your simple sentence of "I want to sleep". It is short and you have made your point that you are sleepy. Sometimes you just don't need an object to create a complete sentence but the way you said might trigger some readers to ask you "why". It is a fine sentence but you still have a lot of rooms to make it better.

Hope this help!

首先要講的是，句型並不一定是SVO，又是可以是SVC，如
I am happy
而最簡單的句型是SV，如：
He came
再回到你的句子，I want to sleep，這句子的句型不錯是SVO
而to sleep是不定詞(to-infinitive），在這句作為受詞(object)
不定詞的應用非常廣泛，可作主詞，如：
To know oneself is very difficult.
也可以作受詞，如：
They ceased to laugh.
甚至可以作形容詞，副詞等
所以，你的示句並非有兩個動詞

再者，並不是一句句子只有一個動詞，就像complex sentence和compound sentence，因為是由兩句子句組成，故可以有兩個動詞
與其說一句句子只有一個動詞，不如說一句子句只有一個動詞更為清楚。

希望幫到你！

2009-09-07 14:40:16 補充：
003所講不可一概而論 ,就如
Longman Dictionary of Contemporary English(英文版) ,在breakfast條下,就有一例

I never eat breakfast.
可見eat breakfast, eat lunch, eat dinner同是外國人用語

除非編寫這字典的是中國人(看來機會微乎其微)

句子唔一定有object既, 所以 "i want to sleep" is ok

yes, each sentence can only have 1 verb, but u can put "to" in front of the 2nd verb, or make the 2nd verb in the form of "ing":

e.g i like sleeping (i like to sleep), i like shopping (i like to shop)...