Because natural disasters occur at random times, it is difficult to warn people _______.
#26129
A
at present
B
at last
C
on time
D
in advance
推荐题目
The little boy felt grateful ________ the coach for his letting him ________ the game. 
#27220
A
for / join in
B
to / to join in
C
with / join
D
to / join in
 He is always helping people without expecting anything _____.
#26277
A
in common
B
in turn
C
in danger
D
in return
My brother is very good ___ ping-pong.
#28850
A
in
B
for
C
at
D
on
Dr. Black is a professor of chemistry. _______, he is a famous writer.
#26684
A
In all
B
In brief
C
In fact
D
In addition
Research universities have to keep up with the latest computer and scientific hardware __________ price. 
#27260
A
on account of
B
in addition to
C
regardless of
D
not to mention