64匹赛马每次只能赛8匹,最少需要几次可以决出所有赛马的名次?设定每匹马的速度是固定的.

下列各句中，没有语病、句意明确的一项是（）

A．近年来骑马爱好者剧增，使得赛马运动发展迅速，相应的，一些骑马俱乐部也应运而生。

B．他饰演了一个英雄人物，观众被深深打动了，说这是我们的偶像。

C．在引进竞争机制的情况下，如果还想捧着“铁饭碗”不放，那就是一厢情愿。

D．艺术教育无论在德育、智育，在人格的完善、性情的陶冶等方面都是教育行为中的一个重要组成部分。

Jockeys(职业赛马骑师) are the smallest athletes. They are rarely over five feet six, or 120 pounds. The lighter the weight on the horse, the faster it can go.
Riding fast horses on the track is tough on the small jockeys. The jockey doesn’t“sit”on the horse. He leans forward on his legs. The strain is on his thighs(大腿) and calf(小腿) muscles. As jockeys age, their legs“go”first. Jockeys also need arm strength. It’s a strain holding a 1000-pound racehorse.
On muddy days, jockeys get a pounding of mud. The mud comes flying off the hooves(蹄) of the horses in front. “It feels like someone is punching you all over,”says one rider.
And a jockey can be hurt. A jockey can have a leg jammed between two horses. Or it can get caught between horse and the rail. The worst accidents are from falls. A horse may fall on his rider. Or horses behind may trample if he hits the track. In one year about 240 riders are hurt badly. That’s one out of six jockeys.
But the jockeys are well-paid. A jockey keeps about ten percent of the money his horses win. Jacinto Vasquez, a five-foot-three comer, has ridden horses to ＄7,000,000 in wins in the last eight years, which means he does almost ＄100,000 a year.
Why do some jockeys do better than others? “It isn’t the way a boy sits on a horse or uses the reins or the whip,”says Conn McCreary. McCreary was a top jockey of the 1950’s. He rode two Kentucky Derby winners. “Most jockeys do this the same. It’s the ‘feel’ he has for the horses.”
“When you come right down to it, it just seems that horses run better for some riders,” McCreary says. “A real good jockey doesn’t lose with the best horse. And sometimes he’ll win with the second or third best.”
Many Latin-American riders, like Jacinto, seem to have the knack . “Maybe it’s because we grew up with horses,”says Jacinto. “Maybe it’s because we like to ride. There was a strike at Aqueduct last year. We, Jorge Velasquez, and Angel Cordero (two other top Latin riders) went to a park. We rented horses, and rode around the bridle path(骑马专用道)!”
小题1:The main idea of Paragraph 1 is about ______________.

A．the size of jockeys.	B．the age of jockeys
C．the size of the horse	D．the speed of the horse

小题2:When a jockey is riding a fast horse, he doesn’t __________.

A．really sit on the horse	B．lean forward on his legs
C．use much arm strength	D．get any mud on wet track

小题3: The most dangerous problem for a jockey arises __________________.

A．when his leg is jammed between two horses

B．when his clothes are splashed over with mud.

C．when the jockey’s horse falls on the jockey

D．when the jockey is not well paid

小题4:A really good jockey can often win a race ____________.

A．only when he rides on the best horse

B．even when he rides the second best horse

C．when he rides on a rented horse

D．if the horse is just a Kentucky Herby

小题5: The underlined word “ Knack ” in the last paragraph probably means__________________.

A．special skill	B．dangerous hobby
C．riding culture	D．excellent horses.