给定文法G[E]:E→E+T∣T T→T*F∣F F→(E)∣i, 则以下( )全都不是规范句型的活前缀 ①T+ ②T* ③ε ④T*F ⑤E+E ⑥E* ⑦E+ T* ⑧i ⑨(E+T) ⑩(i)
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
免费的网站请分享给朋友吧