Parents often wonder what effect thumb sucking or sucking on a pacifier might have on their baby's teeth.

VOA: special.2009.03.11

I said that if I was really hygienic, and you can now wonder about how often do I shower?

但是这真的很棒，对不对？,那么为什么我要说这些呢？,我说过如果我真的很讲卫生的话？

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