图示多跨梁剪力为()。
A.M/a
B.-M/a
C.2M/8
D.-2M/aMM
参考答案:B
“春蚕到死丝方尽”是古人的误解。其实,蚕吐尽丝时并未死亡,只是发育成不吃不动的[ ]
A.卵
B.幼虫
C.蛹
D.成虫
----- The flower is beautiful. ----- _________.
A.So is it
B.So it is
C.It is so
D.So it is