英语情景对话答案17.I've never been to HongKong before.How many times

英语情景对话答案
17.I've never been to HongKong before.How many times have you been there?
18.How long does it usually take you to do your homework in the evening?
19.If you want to post some letters and presents to your friend,where can you go?
20.I'm going to celebrate my 15th birthday this weekend.When is your birthday?
21.One ticket costs 5 yuan.How much should you pay for three ticket?