giúp mk vs ạ 36. It is necessary for you to do your homework every day. You have ………………………………………. 37. Nam is only seventeen years old. He can’t drive a car. Nam isn’t ……………………………………… 38. The river is not clean enough for us to swim in. The river is …………………………………………… 39. I had a dog last year but I don’t have any more now. I used to …………………………………………………….. 40.Putting a knife into an electrical socket is very dangerous. It’s………………………………………………….. 41. John smokes a lot a year ago, but now he doesn’t smoke any more → John used …………………………………………………………………………………………………………………………… 42. It’s time for you to go to school → It’s time you ……………………………………………………………………………………………………………………………