51. You (receive)………………….any letter from your parents yet? 52. My brother (join)…………the army when he (be)……….young. 53. I (see)……. a car accident while I (wait)………..for you at this corner yesterday. 54. Mr.John (be)………..principal of our school since last year. 55. Mr. Smith (teach)…………….at this school since he (graduate)………………..in 1990. 56. My father (not watch)……….TV every night. 57. I (meet)…………………. Arthur 3 weeks ago. 58. Yesterday the police (report)…………that they (capture)……………………..the thief. 59. My friend (thank)…………………me for what I had done for him. 60. Someone (steal)………….. my handbag on the bus giúp mk với