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"Open wide... Now this won't hurt a bit..."

Ouch! No-one likes a visit to the dentist…

But when do we say 'open wide' and when do we say 'wide open'?

And what's the difference between 'wide' and 'widely'? Li explains.

If you have a question you'd like us to answer, you can write to us or email: questions.chinaelt@bbc.co.uk