87. If you ……………….. the lesson, I’ll explain it again to you. (not understand) 88. If the rice paddies …………………., the rice plants ………………… (pollute / die) 89. John ………………… the first prize in the English speaking contest. (just / win) 90. Uncle Ho devoted his life …………………. the independence for Vietnam. (gain) 91. I think we …………………… some canned food before typhoon. (buy) 92. I suggest …………………… solar energy instead of coal, gas and oil. (use) 93. Why not ………………… another products ? (choose) 94. Let her ……………… her best to finish her work in time. (try) 95. Unfortunately, he ………………….. three accidents recently. (have) 96. A new photocopier …………………. in last week. (put) 97. He would be healthier, if he ……………… so much. (not, smoke) 98. Road users …………………… by law to wear quality safety helmets. (force) 99. Please wait right here until Katie …………………… back. (come) 100. His daughter is interested in ………………… with Barbie dolls. (play) 101. Mrs. Linda is busy ………………….. Christmas tree. (decorate) 102. They are the first customers ………………… and ………… things in the shop. (come / buy) 103. Do you have difficulty ………………….. a job after …………………. ? (find / graduate) 104. It was impossible to use fire-fighting equipment because most of the water pipes …………… before. (burst)