列车客室内和车门附近应有足够数量的()或()。
参考答案:扶手杆(环);把手
—I'm afraid I can't return he the book to you before Tuesday.
—________.[ ]
A. Don't be afraid
B. You are welcome
C. Take your time
D. Be careful
My mother is ______ English teacher. [ ]
A. a
B. an
C. the
D. /