①How much are these socks?---Two dollars ___ one pair
问题描述：
①How much are these socks?---Two dollars ___ one pair
②We have watches ___ red and black
③for ,they ,one ,only ,$5 ,pair ,are
______________________________
④vegetables ,good ,they ,very ,all ,prices ,the ,at ,sell ______________________________________________
答
for
in
They are only $5 for one pair.
They sell all the vegetables at very good prices.