单项选择题
A．was not taken B．were not taken C．didn't take D．haven't taken
Since the introduction of the new technique, the produc...
单项选择题Since the introduction of the new technique, the production cost（）greatly.
A．reduces B．has been reduced C．is reducing D．is reduced
I'll take down your name and address in case you（）as a ...
单项选择题I'll take down your name and address in case you（）as a witness.
A．are needed B．have needed C．need D．were needed
The riot is said（）by the government's negligence of the...
单项选择题The riot is said（）by the government's negligence of the people's welfare.
A．to have been caused B．being caused C．to be caused D．to cause
