11 john hasn't been seen when he was leaving for edinburgh
12 john has been a television presenter for five years
13 my uncle started working in that factory was 10 years ago
14 when did your family read Tuoi Tre newspaper?
15 since 2005 my old friend has worked on that farm
16 how long has he taught physical education in this school?
17 My mother had this washing machine a long time ago
18 My father hasn’t drunk champagne for 10 years
19 Jane’s grandma stopped planting trees in the garden 5 months ago
20 My mother is the most warm-hearted person I have ever met
