【单选题】
文法G【S】=（{b}，{S，B}，S，{S→b│bB，B→bS}），该文法所描述的语言____。
①
L(G[S])={b2i+1│i≥0}
②
L(G[S])={b2i+1│i≥1}
③
L(G[S])={bi│i≥0}
④
L(G[S])={b2i│i≥0}
【单选题】
Once our chickens started laying eggs, we had such a
____ of eggs that we were giving many away to our
neighbors.
①
output
②
surplus
③
production
④
plenty
【单选题】
Once our chickens started laying eggs, we had such a _____of eggs that we were giving many away to our neighbors.
①
output
②
surplus
③
production
④
plenty
【单选题】
6. –Look, someone is coming. Guess who it _____ be?–I think it _____ be Tom.–I don’tthink it _____ be _____.
①
must; can; must; his
②
may; can; must; him
③
must; can; him
④
might; must; can; himself
【单选题】
By no means_____ to our plan for the trip.
①
will she agree
②
she will agree
③
agrees she
④
will agree she
【单选题】
Bob is one of the [填空] in our school.
①
foreigner
②
foreigners
③
foreigneres
④
foreigneries