在3种不同类型的组合框中，只能选择而不能输入数据的组合框是______。
参考答案：下拉式列表框
Father has had the computer _________. Now it works very well.
A．repair
B．repairing
C．to be repaired
D．repaired
钢板对接接头受切应力，当焊缝长度L=200mm.板厚=10mm时，求该焊缝所能承受的切力为多少？[τ’]=100MPa
