To give a short answer to a question with the verb want, we say:
Do you want to come with us?
-Yes, I do.
Is it also possible to say:
Do you want to come with us?
-Yes, I want to.
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Sign up to join this communityTo give a short answer to a question with the verb want, we say:
Do you want to come with us?
-Yes, I do.
Is it also possible to say:
Do you want to come with us?
-Yes, I want to.
As a native speaker of American English, I would most likely say
Yes, I do.
I could be a little more emphatic and say
Yes, I sure do.
If I wanted to use want I would most likely still use do:
Yes, I do want to.
But I would not say that often, and usually only when some person or some circumstance has cast some doubt on whether I want to.
The other option
Yes, I want to.
is not wrong, but it is probably the version I would least likely say. I may use it when I want to come but can't actually do so:
Yes, I want to, but I can't.
Instead of Yes, I do want to I could also say
Yes, I do do.
which means the same (emphasizing that I do actually want to go). However, this can be problematic, as do do sounds like doodoo, which is a slangy, child directed, or childish synonym of poopoo (excrement). So I wouldn't advise saying this unless you and the people you are talking with averse to any reference to this homonym, unless you wish to make a childish joke.