有幾個英語時態(tài)的選擇搞不懂,
1.An unexpected heavy rain caused severe flooding,and the water_____all the time.
A.rose B.raised C.was rising D.was raising
（為什么選D不能選C）
2.--What are you doing under the table?
--I____to find my watch.
A.tried B.try C.am trying D.have tried
(為什么選D不能選C)
3.I will ask her for the book now,for she_____plenty of time to read since I lent it to her.
A.has B.has had C.had had D.was having
(為什么選B不能選C）
4.We are late.I expect the film will already have started by the time we get to the cinema.
A.will already have started
B.would already have started
C.shall have already started
D.has already been started
（為什么選A不選B)