修建圆形的沼气池好，还是方型的好？
参考答案：
圆形的好。（因为圆形比长方形的表面积小，省工、省料；受力均匀，池体牢固；内壁没有直角，容易解决密封问题。）
But the unpleasant feeling of coldness disappeared at the _______ of his students pouring out of their classroom to give him a warm, wordless welcome.
A．sight
B．scene
C．view
D．Sign
“四始”说出自司马迁的《史记·孔子世家》，他以《关雎》为国风之始（）为小雅之始，《文王》为大雅之始，《清庙》为颂之始。
