1 I think watching birds is interesting
2 Nick doesn't have flu because he washes his hand a lot
3 You should eat less junk food
4 I have helped the street children for 2 years
5 Would you mind taking me to the airport Friday morning
II
1 Have you ever done any volunteer work
2 If we eat too many, we can get fat
3 Many volunteers have collected used books and clothes for street children
4 You should spend less time playing computer games
5 There are some bottles of water in the fridge
III
1 Last year we started our community project
2 It is very difficult for me to lose weight