Put the verbs in drackets into the correct form / Make the sentences negative

1. a) jack (has told) us two funny stories since he (came) here. b) jack (has told) us two funny stories since he (has been) here. 2 a) i have liked him since i (have known) him. b) i (have liked) him since (i met) him. 3. a) since i (have had) this car (i have repaired) it three times. b) since (i bought) this car (i have repaired) it three times. 4. a) since we (have known) him he (has been) very helpful. b) since he (began) working here he (has been) very helpful. 5. a) my dog (has given) us twenty puppies since we (have had) her. b) my dog ( has given) us twenty puppies since we (took) her.

Teenagers from America are not really different of teenagers from other countries. They have almost the same interests such as sport, computers and TV. They spend most of their free time playing with their gadgets or just watching TV. Of course, they go to the cinema, clubs with their friends. They visit sport grounds because a lof of American teenagers are fond of sport like basketball, football, some physical exercises and so on. 
All in all, they have really active lifestyle and that is great!