When are windows the weak link in a building?

A．In the cold winter.

B．In the hot summer.

C．When air conditioners are turned on.

D．Both Ａ and Ｂ.

[单选题]If you do not use your arms or your legs for some time, they will become we

[单选题]If you do not use your arms or your legs for some time, they will become we

[单选题]If you do not use your arms or your legs for some time, they will become we

[单选题]If you do not use your arms or your legs for some time, they will become we

[单选题]If you do not use your arms or your legs for some time, they will become we

[单选题]The headmaster wanted the classroom building__________as soon as possible．A．to set upB．to have been set upC．to be set upD．being set up

[单选题]2． The mother is ________weak _________look after her little daughter．A． too ,toB． so ,thatC． very ,toD． so ,to

[单选题]［A］ comfortable ［B］ weak ［C］ risky ［D］ firm

[填空题] XO系列电梯各串行末端必须安装（），C-Link，H-Link，G-Link必须齐全。

[名词解释] Host Link