In the bedroom, you are told______.
A. not to use an electric underblanket or an electric overblanket
B. to use an underblanket of the low voltage type
C. to switch off an underblanket of the low voltage type
D. not to use an electric underblanket over you
What does city growth result in？
A definite degree of planned order.
B. Uniform. growth throughout the city's area.
C. A systematic pattern of restoration.
D. An aimless growth of new areas over old.
班级授课制在我国正式实行一般认为是在 ()
A. 唐朝中期
B. 明朝中期
C. 清朝末年
D. 辛亥革命后
Barter usually takes the place of money transaction where______.
A. there is only salt
B. metal tools are used
C. the people's trading needs are fairly simple
D. money is unheard of
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