26/It ______________ quite often in Britain during the winter. * is snowing snows snowed was snowing 27/While I was going to school yesterday, I ____ him. * meet met will meet am meeting 28/My son was sleeping when I ______ home. * went has gone had gone would go 29/This morning while I ______ for the bus, the rain stopped. * waited have waited had waited was waiting 30/I ___________________ Mai for five years. I wonder where she is now. * don’t see hadn’t seen haven’t seen didn’t see 31/Mr. Harry ______ in the army from 1980 to 1985. * had served has served is serving served 32/Andrew _______________ the test before so he _____________ it very easy. * did / had found was doing / found had done / found did / was finding 33/Water ___________________ at 100 degrees Celsius. * is boiling boiling boils boil 34/When he ____________ at the station, his train already _____________ . * arrived / left arrived / had left had arrived / left arrives / leaves 35/Phong ______ at the university so far. * had worked was working worked has worked 36/We _____ in this house for ten years. * are living were living had lived have lived 37/Bettie usually ___________________ television in the evening. * has watched watching watches watch 38/___________________ to rain before you woke up this morning? * Did it begin Had it begun Has it begun Began 39/While I __________ in the street, I saw my old friend. * was walking am walking walk walked 40/Ann ___________________ very hard at the moment. * has studied studied is studying studies 41/My daughter saw an elephant this morning, but she ___________________ one before. * had never seen has never seen never sees never had seen 42/By the time we got to the market, all the shops ___________________ . * have closed were closing had closed closed 43/We ___________________ any interesting films lately. * didn’t see haven’t seen saw have seen 44/It was midnight. Outside it ________________ very hard. * rains is raining rained was raining 45/Up to now, the pollution problems ________________ yet. * haven’t solved are not solving hadn’t solved will not have solved 46/Up to the present, Nam_____ good work in his class. * does has done had done did 47/Pasteur ___________________ in the 19th century. * was living lived had lived has lived 48/The phone ___________________ suddenly while Jane was doing the housework. * rang was ringing had rung is ringing 49/Yesterday when I _____ at the station, the train _______ for 15 minutes. * arrived/ had left arrives/ has left arrived/ left had arrived/ left 50/The manager ___________________ a letter when I interrupted him. * has read reads was reading read