英语句子四道!1.Perhaps thet may find ______the clouds have changed

英语句子四道!
1.Perhaps thet may find ______the clouds have changed ______the last few hours.
A.when B.if C.that D.why
A.through B.during C.since D.from
2.This may ______that the weather on the ground may soon ______,too.
A.decide B.believe C.hope D.mean
A.stay B.remain C.change D.turn
3.In the ______they could forecast the weather for about 24 or 48 hours earlier.
A.end B.past C.future D.time
4.Soon,______ ,they may be able to forecast the weather for a week or more ahead.
A.but B.though C.perhaps D.so far
第一题中的”thet”改为”they"