题目

—Where ______ the boys? —______ in the room. A．is；It's                  B．are；They're           C．are；He's              D．is；He's 答案：B13．从南极到北极，纬线长度变化的规律是（　　）A．逐渐变长B．逐渐变短C．由长变短再变长D．由短变长再变短