问题
选择题
Listen! There’s a lot of noise from next door. They _____________ a party.
A．could have had
B．must be having
C．should have had
D．can be having
答案
答案：B
考察虚拟语气.句意:听!隔壁有很多噪音.他们一定是在举行一个聚会.must be表示对现在的情况的肯定地推断,故选B.