问题补充：
John to Japan on business. He’ll be back a few days.
A. goes; in
B. went; after
C. has gone; in
D. go; after
答案：
A. goes; in
B. went; after
(答案→)C. has gone; in
D. go; after
解析：句意:约翰已经出差去了日本.他将在几天后回来.结合语境可知前文描述的是现在已经完成的动作,故用现在完成时态.下文描述的是将来某时进行的动作,故时间状语表示将来时态,in后接一段时间表示在多久之后,after后面一般接时间点,故选C.
