如图,在平行四边形ABCD中,BC=2AB,CE⊥AB于E,F为AD的中点,若∠AEF=α,则∠B=().

如图,在△ABC中,M为BC中点,AN平分∠BAC,AN⊥BN于N,且AB=10,AC=16,则MN等于()

CB,CD分别是钝角△AEC和锐角△ABC的中线,且AC=AB.则CE与CD的数量关系是()

如图,在四边形ABCD中,点P是对角线BD的中点,点E、F分别是AB、CD的中点,AD=BC,∠PEF=30°,则∠PFE的度数是()

顺次连接对角线相等的四边形各边中点所组成的四边形是()

梯形的上底长为a,下底长是上底长的3倍,则该梯形的中位线长为()

如图,在直角三角形ABC中,∠C=90°,AB=10,AC=8,点E、F分别为AC和AB的中点,则EF=()

补全对话
A: Hi, Sand, what are you going to do this weekend?
B: I’m going to see a movie. Can you give me some advice?
A: Sure.1                ?
B: I like action movies.
A:Have you ever seen the movie Avatar（阿凡达）？
B：2                 .But I heard it is great.
A: Oh, I saw it yesterday.
B: 3                ?
A: I think it is the best movie I have seen.
B: 4                ?
A: It lasts about two and a half hours.
B: Is the ticket price high?
A: Yes. Watching it in 3D costs 120 yuan.
B: 5                   .
A: You’re welcome.

补全对话
A: Good afternoon, Tom. Where are you going?
B: 1             .
A: Oh, to buy books? You are out! Why not go to the Readers' Room?
B: The Readers' Room? 2                .
A: It is a place where students can exchange their old books with others.
B: That sounds great! 3               .
A: It's next to Renmin Hospital, across from City Park.
B: Oh, it's a little far. 4                .
A: You can take No. 7 bus.
B: How long does it take?
A: 5               .
B: Ten minutes isn't a long time. OK, I will go there. Thanks!

补全对话
A: Hi，David!1          ? ?
B: Hi，Sarah! I am going to see Anna. She is in hospital.?
A: 2        ?
B: She had a traffic accident on her way to school and was hurt.?
A: 3         . Is there anything serious??
B: Yes, there is something wrong with her head.?
A: Oh, my God! 4         . ?
B: I hope so, too.?
A: 5            ? ?
B: Sure. Let’s go!?