单项选择题
A．It can be cooked in many ways. B．It is delicious but inexpensive. C．It gives higher yields than other grain crops. D．It grows easily in various conditions.
A．He didn’t like physics any more. B．His eyesight was too poor. C．Physics was too hard for him. D．He had to work to support himself.
A．To protect persons and property. B．To collect taxes. C．To teach and train citizens. D．To save natural resources for future use.