单项选择题
Mack is very busy; he is a full-time student, while______ a part-time job.
单项选择题 -Who is late this time -______you ask Susan, of course.
单项选择题 I'11 send you my address______ I find somewhere to live.
单项选择题 -Your sister looks beautiful. Is she a model or a film star -______. She's a doctor.
