我是名高三生,希望能够快点得到答复!

我是名高三生,希望能够快点得到答复!
1.I ____ from the crowed an old friend of mine whom I hadn't seen for 10 years.
A.figured out B.picked out C.gave out D.went out
2.---Who gave you this message?
---A man ______ himself Mr Zhang.
A.called B.calls C.is called D.calling
3.If you want to see a doctor,you'd better make an appointment with him.This is a common ___ in the USA.
A.sense B.practice C.habit D.attitude
4.You can come to the dance ___ you dress.
A.whatever B.whichever C.whether D.however
5.We got near a garden ,____ owner sitting in it.
A.its B.whose C.that D.which
6.If the horse won today,it___30 races in 5 years.
A.wold have won B.won C.must have won D.has won
以上六题答案为BDBDAA,为什么呢?