Question

Fill in each gap with WH word (how,which,who,what,where) I know a place _____ you can by fresh flower
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Answer 1

The answer for your question is where.

Answer 2

Answer: I know a place where  you can buy fresh flowers.

Explanation:

If the sentence specifies some place then suitable word is where

If the sentence specifies some time then suitable word is when

If the sentence specifies some thing then suitable word is which

If the sentence specifies some way of action then suitable word is how

If the sentence specifies some person then suitable word is who