隋朝灭亡的主要原因是[ ]
A、土地兼并严重
B、奢侈腐化，滥用民力
C、法律严酷
D、宦官专权
答案：B
Opposite my school _______ a book store, _______ was built ten years ago.
A．is standing, which
B．stood, it
C．stands, which
D．stands, that
击实试验的原理与压缩实验的原理一样都是土体受到压密。( )
