题目

Not only        interested in football but        beginning to show an interest in it. A、the father himself is; all his children are    B、the father himself is; are all his children C、is the father himself; are all his children    D、is the father himself; all his children are 答案：D如图所示的用具中，属于省力杠杆的是（ ）A．B．C．D．