help em ik mn ơi 
Câu bị động 
1 . My father took me to Ho Chi Minh last week .
2. A man returned the keys to me .
3 . Mary saw her friends off at the station .
4 . He prepared everything for the president election .
5 . Last Friday , she finished all exercise .
6 . They pull down that building .
7 . He gave me a knife to cut this bread .