一般过去时：
1.The bridge was built last year.
2.I was born in 1999.
3.The door was broken by the thief last night.
4.Two cars were damaged in the accident.
5.100 million of money was spent on the building.
过去完成时
1.The thief had been caught by the police.
2.The books had been sold out.
3.They had been to Beijing for twice.
4.My homework had been finished.
5.The letter had been sent .
现在进行时
1The bridge is being built now .
2.The classroom is being cleaned by the students.
3.Dinner is being cooked by my mum now.
4.Cartoons are being watched by children on TV.
5.The housework is being done by my mum now.
