Mike and Dick work in the same office. They don't like the cold weather. And one day they decided to take their holiday in Australia. Their plane arrived in Sydney at nine in the morning. They had a good rest in a hotel(旅馆). The next morning they rented(租) a car in the city and began their travel. A few hours later the sun was shining in the sky and there were no shade trees (遮荫树) beside the road. It was so hot that they could hardly go on driving. They had to stop to look around. Mike found a river was about half a kilometre away from them. They were both very happy and drove the car quickly. Soon they got to the river. Before they jumped into the water, Dick saw a boy playing under a big tree. He asked, “Are there any sharks (鲨) in the river, boy?” “No, there aren't,” answered the boy. So they began to swim in the river. After a while, Dick felt something hit against his leg. He told Mike about it. They were afraid and stopped swimming. Dick asked loudly, “Is it true that there aren't any sharks in the river?” “Yes, sir,” said the boy. “There're a lot of crocodiles(鳄鱼) in the water. All the sharks have swum away!”

1．The story happened when it was ________ in the two men's country.

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2．Mike and Dick went to Australia ________.

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3．The two young men went to Australia to ________.

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4．Mike and Dick couldn't drive any longer because ________.

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A．the sun was shining in the sky

B．there were no shade trees beside the road

C．the weather was very hot

D．they were too tired

5．Dick became afraid because ________.

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A．he saw a shark in the water

B．he thought it might be a shark that hit against this leg

C．he saw the boy laughing at the munder the big tree

D．he had been told there were some sharks in the river

6．Having heard the boy, the two young men began to ________.

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A．catch the crocodiles in the water

B．look for the crocodiles there

C．to beat the Australian boy

D．come out of the river at once