12)We have lived in Hanoi for ten years now and like it a lot.
13)The last time I went to HN was in May
14)When my parents were on holiday I stayed with my aunt for a week
15)I haven't seen my son for ages .He hasn't visited me since May
16)Tom has been to HN twice .He loves it very much
7)My sister has worked for an enterprise for two years .That was after college
18)I moved to HN in 2001 .I have been there a long time now
19)It was so cold today that I have worn a sweater at school
20)So far this month there has been three robberies in this street
21)When I was young I met him three times
22)In the past few years ,it became more and more difficult to get into university
23)I felt better since I have lived here
24) Since I was in this city I have not seen him