三角形容易变形．______．
三角形具有稳定性，不容易变形，
故答案为：错误．
∠A与∠B互为余角，∠A=35°，那么∠B的补角=______．
The boy ought to have gone to school ___, but he slept ___noon.
A．in the morning, at
B．that morning, at
C．in that morning, until
D．that morning, until
