问题
选择题
We always keep ____ gas in case we run out.
A．a great number of
B．plenty of
C．much too
D．a good many
答案
答案：B
句意：我们总是保持足够的天然气以免用完。a great number of修饰可数名词复数；plenty of既能修饰可数名词又能修饰不可数名词；much too 过分，太；a good many修饰可数名词复数。因为gas是不可数名词，所以选B。