(If) you (will buy) one box at the regular price, you would receive (another one) at (no) extra cost.（）

单项选择题The (scientific) revolution of the early 1900s (affected) education by (change) the nature of (technology).（）

A．scientific
B．affected
C．change
D．technology

单项选择题New York City's first large electric sign, (which was) over six stories (high) and topped by a (forty-feet-long) green signboard, (appeared) on the side of a building in 1900.（）

A．which was
B．high
C．forty-feet-long
D．appeared