木材横纹抗剪强度很（），只有顺纹抗剪强度的（）左右，截纹抗剪强度约是顺纹抗剪强度的（）倍
参考答案：低；1/2；3
The people in the war area have _______food. They are in a very difficult situation.
A．run out
B．used up
C．been run out of
D．been used up
