单项选择题
A. places where the police hide in order to trap motorists B. dangerous parts of the road which are not easily noticed by drivers C. danger spots such as sharp corners and cross-roads D. places where there are too many road-signs
A．would make the same achievements in a course B．would do poorly with his study C．would develop his individualism and limit his intelligence D．would eventually leave shcool
A．watch for B．help with C．teach individually D．drop