chọn đáp án đúng (thì bị động ) 1.the flight attendant reminded the man that smoking .......there (allow) 2.america ..... by colombus in 1492(discovere) 3.parrots and crows ..... the most intelligent birds (consider ) 4. i still can't believe ! my bicycle ..... last night (steal ) 5.many traffic accidents....by dangerous driving (cause) 6.grass ...... by fat cows on the green meadow (eat) 7.so much progress........that there may be space -flights to mars (made) 8.english ....since 2002 (learn) 9.your bill should ....before you leave the hotel (paid)