Quan sát dưới gầm các ô tô chở xăng bao giờ ta cũng thấy có một dây xích sắt. Một đầu của dây xích này được nối với vỏ thùng chứa xăng, đầu kia được thả kéo lê trên mặt đường. Hãy cho biết dây xích này được sử dụng như thế để làm gì? Tại sao?

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1.If you park your car in wrong place you have to pay a .................................A. ticketB. attention C. fee D. fine2.Our flight from Amsterdam to London was delayed .............................. the heavy fog.A. because ofB. in spite ofC. asD. though 3.The wall was covered ........................ posters advertising a few films .A. in B. forwardC. with D. from4. Remember to turn off the lamps before leaving . ...................... cost us too much .A. Air conditioning B. Water C. Lighting D. Heating5. Why didyou stay an extra day in Paris? A. Good ideaB. Thanks for inviting me to stay an extra day .C. I promise I ‘ll do that.D. I’m busy now . I’ll tell you tomorrow . 6. I love volleyball ....................... I must complete my homework .A. andB. soC. butD. or7. Some people have .................... the tourist attraction . They litter , pick flowers and walk on the grass .A. foamedB. protectedC. preservedD. spoiled8.If crops ___________ with pesticides, they will be destroyed by insects in soil.A. doesn’t sprayB.aren’t sprayedC. are sprayedD. will not spray9.“I suggest fixing the dripping faucet”-__________________A. We willB. Good idea C. Yes, pleaseD. I’m afraid not 10.This man __________ heavily yesterday for cutting down the trees in the forestA. was fineB. fined C. had fined D. was fined 11._______________the pollution in that river is awfully bad, the water is not fit to drinkA. Because of B. Although C. SinceD. If 12. Don’t drink that water. It’s ________.A. contaminated B. damaged C. dumped D. cleaned13. The team’s success was largely ________ to her efforts.A. since B. due C. because D. lead