It took a mere twenty-year flick of time to double the limit again. And by the 1960’s rocket planes approached speeds of 4000mph, and men in space capsules were circling the earth at 18,000mph.Whether we examine distances traveled, altitudes reached, or minerals mined, the same accelerative trend is obvious. The pattern, here and in a thousand other statistical series, is absolutely clear and unmistakable. Thousands of years go by, and then, in our own times, a sudden bursting of the limits, a fantastic spurt forward.

[单选题]This college graduate tried our company a third time, _____ to be turned do

[单选题]Passage ThreeIt's Christmas again. We live on a dirty street in a shabby house among people who aren't much good. You can't see how pitiful it is that our neighbors have to make happiness out of this filth (污秽) and dirt. My children must get out o

Its a good idea to ______ those old cars into use again.（ ）A. makeB. bringC. tak

[单选题]A twenty-year $1,000 fixed rate non-callable bond with 8% annual coupons cu

[单选题]We haven’t found the missing paper， and let’s( )through the room again.A.pa

[问答题]You’d better do that again.

[问答题]Promise me never to be late again.

But if I ______, I would try again.A. should failB. would failC. failedD. had fa

[单选题]Only when the rain stopped， ( )again.A.the sports meeting startedB.has the

[主观题]—You forgot (close) the window again.—Really? I won’t next time.