Yang Liwei’s journey into space took him 600 000 kilometres in orbit around the earth 1

问题补充：

Yang Liwei’s journey into space took him 600,000 kilometres in orbit, around the earth 14 times, in just over 21 hours.

A. a, an

B. the, an

C. 不填，不填

D. the, the

答案：

A. a, an

B. the, an

(答案→)C. 不填，不填

D. the, the

解析：考查冠词的用法。句意“杨利伟在太空遨游了600000公里，用时21小时，绕地球14圈。”space前不加冠词，in orbit“在轨道上”。故选C。