It’s getting late. We must "be off" now. Which of the following can’t replace the underlined part?

　 A. begin 　 B. be leaving  C. start 　 D. go

　　Now, Julie's team ran up and down over the snowy hills. They　 5　 only to rest and eat. They wanted to stay　 6　 of the other teams. The racers had to go a thousand miles across Alaska. Alaska is one of the　 7　 places on Earth. The dogs' thick fur coats helped　 8　them warm in the cold wind. In many places along the way, the snow was deep. Pieces of ice were as　 9　 as a knife. The ice could cut the dogs' feet. To keep that from　 10　 , Julie had put special boots on their feet.

　　At first, the dogs seemed to　 11　 the sled very slowly. They were　 12　 getting used to the race. But on the third day out, they began to run more　　13　 . They worked　 14　 a team and passed many of the other racers. Once, one of the sled's runners fell into a hole and 15　 . Julie could have given up then, but she didn't. She fixed it and they kept going.

　　When they finally reached the finish line, they found that they had come in first place! It was a great day for Julie and her dogs.

It’s getting late. We must "be off" now. Which of the following can’t replace the underlined part?

　 A. begin 　 B. be leaving

　 C. start 　 D. go

It’s getting late. We must "be off" now. Which of the following can’t replace the underlined part?

A. begin 　 B. be leaving　 C. start 　 D. go

The dogsled race was about to begin. Julie's team of dogs was lined up at the starting gate. Julie stood behind them. Other teams were 　1　 up, too, and the dogs were excited. Julie kept her　 2　 on the clock. At exactly ten o'clock, she and the other racers shouted, “Mush!” The dogs knew that meant, “　 3　 !” They jumped forward and the　 4　 started!

　　Now, Julie's team ran up and down over the snowy hills. They　 5　 only to rest and eat. They wanted to stay　 6　 of the other teams. The racers had to go a thousand miles across Alaska. Alaska is one of the　 7　 places on Earth. The dogs' thick fur coats helped　 8　them warm in the cold wind. In many places along the way, the snow was deep. Pieces of ice were as　 9　 as a knife. The ice could cut the dogs' feet. To keep that from　 10　 , Julie had put special boots on their feet.

　　At first, the dogs seemed to　 11　 the sled very slowly. They were　 12　 getting used to the race. But on the third day out, they began to run more　　13　 . They worked　 14　 a team and passed many of the other racers. Once, one of the sled's runners fell into a hole and 15　 . Julie could have given up then, but she didn't. She fixed it and they kept going.

　　When they finally reached the finish line, they found that they had come in first place! It was a great day for Julie and her dogs.