问题
I worked on the problem ____ a long time and I worked it out ____ myself ____ last.[ ]
A: for; by; at
B: in; with; on
C: on; by; in
D:for; for; at the
B: in; with; on
C: on; by; in
D:for; for; at the
正确答案是：
同类题型
Yu Bao was born _____ Nanjing _____ August 16th, 1990.[ ]
Do you have any problems if you __________ this job?—Well, I’m thinking about the working day.
Where is my backpack ? —It’sthe floor . [ ]
His father believe in_____ very much, so he makes decisions all by _____.
Do you know ______ this dictionary belongs to? — Let me see. Oh, it’s _______.