33.---- I'll be waiting for you at home.
---- ____ I were busy and couldn't come?
A.What if
B.What when
C.How if
D.How when
32.The difficulty we now meet with is ____ we can persuade him to tell the truth.
A.whether
B.that
C.what
D.how
31.The boy was criticized for forgetting ____ his textbooks to school.
A.bringing
B.to bring
C.having brought
D. to have brought
30.I saw some trees ____ the leaves were black with disease.
A.where
B.of which
C.in which
D.whose
29.That will be the second cigarette he ____ today.
A.smoked
B.has smoked C had smoked
D.would smoke
28.C harles Battage is considered ____ the first computer.
A.to have invented
B.inventing
C.to invent
D.having invented
27.---- Who can take me there?
----____.
A.I
B.Me
C.My
D.Mine
26.He listened attentively to me ____ while____ at me.
A.spoke, stared
B.speaking, staring
C.spoke, staring
D.speaking, stared
25.B ad habits, ____ formed, are difficult to get rid of.
A.and
B.once
C.or
D.but
24.There are No 2 trolley-bus and No 24 motor-bus; ____ will take you there.
A.both
B.either
C.all
D.any