要，想，想要。

[pprendeville]

Can someone explain the differences between these 3. Kinda confused as to when I should be using which. For example should I say 我要写一封信 or 我想写一封信 or should I be using the combination 想要？

[skylee]

我要写一封信 can mean either I have/need to or I want to write a letter, depending on the context.

我想写一封信 means I want to write a letter.

我想要写一封信 also means I want to write a letter, but 要 sounds redundant here.

[tooironic]

I would say 要 by itself is generally more common; 想要, whilst mentioned quite a lot in grammars and the like, is polite and thus, like many polite words in Mandarin, not terribly common.

Note also that 想 can mean "think" or "want" depending on context.

[jbradfor]

Doesn't 要 also have the sense of "will / plan to"?

[shinewind]

#4 is right and it does.

[B-scorpio]

Actually,想、要、想要 they have the same meaning both in formal and oral chinese.

[skylee]

#6, no, not always.