（ ）–It’s raining heavily.Let’s stand under that big tree.

–__________.It’s very dangerous to do so in such weather.

A．We don’t have to

B．Let’s go

C．All right

D．We’d better not

[单选题]It’s raining now. Stop ________ , pleaseA．workingB．workC．to workD．works

[问答题]It's still raining today!

[问答题]()Look out the window it’s still raining today!

[单选题]________ stand her.It’s dangerous.A．NoB．NotC．Don’tD．Doesn’t

[问答题]Look out the window it's still raining today!

[问答题]Look out the window it's still raining today!

[问答题]Look out the window it's still raining today!

[单选题]Let's ______.A.play footballB.play a footballC.play the footballD.play foot

[单选题]Let R and S be the relation respection respectively：Relation R:A B C Relation S:B C D1 2 3 2 3 46 7 8 2 3 59 7 8 7 8 1The number of tuples that the result of the expression R∞S(Here if natural join of relations R and S) is (69) ．(69) A．1B．4C．7D．10

[单选题]Let R and S be the following relations：A．3B．4C．5D．6