要用英语语法知识一个一个说明1.If human beings had been a bit less greedy and cruel,more birds and animals __ dying out.A.ought to avoid B.could have been avoided C.should have avoided D.might have avoided2 As you know,I am a disabled man,but I would be very happy if I __ of service to you.A.would be B.have been C.should be D.am3 I would have come to see you earlier,but I __ _ too busy.A.had been B.were C.was D.would be4 I ___you a valuable present for your birthday

要用英语语法知识一个一个说明
1.If human beings had been a bit less greedy and cruel,more birds and animals __ dying out.
A.ought to avoid B.could have been avoided
C.should have avoided D.might have avoided
2 As you know,I am a disabled man,but I would be very happy if I __ of service to you.
A.would be B.have been C.should be D.am
3 I would have come to see you earlier,but I __ _ too busy.
A.had been B.were C.was D.would be
4 I ___you a valuable present for your birthday,but I was short of money at that time.
A.would have given B.liked to give C.liked to have given D.would like to give.
5.--- Why didn’t you buy the gold ring?
--- I ___but I didn’t have the money.
A.would B.had bought C.bought D.would have
6.--- Could you give me a ride to the City Hall?
--- I _____ _.But I’m late for the meeting on the other side of the town.
A.could B.might C.would D.should