English is not easy, and ________ I like it very much. [ ]
A. so
B. yet
C. but
D. or
答案:B
One of my classmates accidentally ____ he had cheated in the last examination, or he wouldn't have got so
high a mark. [ ]
A. pointed out
B. let out
C. took out
D. tried out
金属材料的性能包括()性能、()性能、()性能和()性能。