Some years ago the captain of a ship was very interested in medicine. He always took medic

ine books to sea and liked to talk about different diseases.

One day a lazy sailor on his ship pretended to be ill. He lay on his bunk(铺) and groaned as if he were very sick. The captain came to see him and was very pleased to have a patient to look after. He told the man to rest for a few days and made the other sailors do his work. Three days later another sailor pretended that he had something wrong with his chest. Once more the captain looked in his medical books and told the "sick" man to have a rest.

The other sailors were very angry because they had more work to do. The patients had the best food and laughed at their friends when the captain was not looking. At last the mate (船长副手) decided to cure the "sick" men. He mixed up some soap, soot(烟灰) , glue(胶水) and other unpleasant things. Then he obtained permission from the captain to give his medicine to the "sick" men. When they tasted the medicine, they really did feel ill. It was so horrible that one of the patients jumped out of his bunk, ran up on deck and climbed the highest place on the ship. He did not want any more medicine.

The mate told both of the men that they must take the medicine every half an hour, night and day. This soon cured them. They both said they felt better and wanted to start work again. The captain realized that the men tried to deceive him so he made them work very hard for the rest of the voyage.

The first sailor pretended to be ill because he wanted to______.

A．test the captain's knowledge of medicine

B．be free from work

C．have the best food on the ship

D．play a joke on his friends