the doctor came to our school _____our teetha.to examine b.for examine c.as to examine d.examine 为什么?

the doctor came to our school _____our teetha.to examine b.for examine c.as to examine d.examine 为什么?
the doctor came to our school _____our teeth
a.to examine b.for examine c.as to examine d.examine 为什么?

the doctor came to our school _____our teetha.to examine b.for examine c.as to examine d.examine 为什么?
the doctor came to our school to examine our teeth
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