单项选择题
A．begin B．started C．know D．hope
A．the bank would always pay money to the forger B．the bank wouldn’t lose any money C．you wouldn’t lose any money D．you wouldn’t lose your money
A．were put forward due to scientists’ recommendations B．came into being as a result of the workers’ demand C．were introduced because quite a number of people were killed or seriously injured D．were effective enough to protect workers and customers