What do you want to be when you grow up-I want to be_______ social worker. Many people are in great need of our help.

__________ did you pay for it— $10.

下列各句中，加横线词语运用正确的一句是（ ）

Do you know the most ancient city in China—Xi’an well?—No，this is the first time I ________ here

下列句子中加点的成语，使用不恰当的一项是