单选题 It made Mary's blood boil to see the children ____ the crippled girl.

单选题 I climbed ____ stairs to come to Miss Gao's office.

单选题 ____, he was the only one who could climb up to the top of the mountain.

单选题 We should ____ animals ____ humanity.

单选题 Tom was so tired that he ____ all the noise without being awaken.

单选题 As a child, he sold newspapers to ____.

单选题 If we can ____ the conditions here, we may get success more easily.

单选题 You will certainly get much improvement if you ____ yourself ____ your studies.