"Use to" or "used to"

[OhLuckyYou]

Which is right? There's an advert for Clover which reads, "Did you use to think crusts gave you curly hair?". It just doesn't look right to me - I think it should be "used to think".

Please tell me I'm right!

Used to, past tense. The other doesn't make sense.

Used, definitely.

The whole sentence just sounds wrong. I couldn't begin to tell you why though.

I would say the 'did you' bit makes it past tense though so I think it's right.

Thank you! I think I will write to Clover and put them straight!!

It shouldn't actually be used in questions, which is why it sounds so wrong I think. It's only spoken, informal language that uses it in questions. Very poor for an advert.

What's wrong with just "Did you think..."?

If it was used in conversation, I don't think you'd notice so much, it's just that when it is written down it looks so wrong.

However, seeing as they are using it in a question, "use to" is correct, as the past tense is indicated by "did".

Yes, it shouldn't be written down in question form, strictly speaking, it's sloppy.

According to this www.bbc.co.uk/worldservice/learningenglish/grammar/learnit/learnitv285.shtml both are correct

Used to.

Well, "Did you used to " definitely isn't correct either- the only way if you really insist on using this phrase is surely "Used you to think...". Shurely?

The advert is correct.

"use to" only exists in the past tense, either as an affirmative, negative or question.

I used to go/Did you use to go/I didn't use to go are all correct and very formal. In informal English, as the beeb site says, we are starting to accept the double negative use of didn't used to etc

Agree with Bucharest.
Affirmative: You used to...
Negative: You didn't use to...
Interogative: Did you use to...?