单项选择题
Without the worker's help, Sam () so much progress.
A. would not make B. would not have made C. will not make D. did not make
单项选择题 He didn't come yesterday. He () busy working in the lab.
单项选择题 It is strange that such a thing () in your company.
单项选择题 He nevcr let me () when I need his support.
