问答题遗传
单项选择题Only twenty percent of the work () done yesterday.
A. has B. was C. have D. were
单项选择题—The research on the new bird flu virus vaccine is challenging and demanding. Who do you think can do the job — () my students have a try
A. Shall B. Must C. Will D. May
单项选择题—Will you be able to finish the job this week —______.
单项选择题I think you've got to the point ______ a change is needed, otherwise you'll fail.