Question

【题目】John's father went to Nanjing ________ten days ago.
A.on duty
B.in business
C.on business
D.on show

Answer 1

【答案】C
【解析】句意：十天之前，约翰的父亲去南京做生意；on duty在值日；on business做生意；on show在展览，根据题意，故选C。