世界上最高的高原形成的地质年代是[ ]
A．新生代
B．中生代
C．古生代
D．元古代
答案：A
A good idea _________ to him, and he knew _______ to do next.
A．happened , what
B．appeared ,how
C．occurred ,what
D．arrived ,how
柔性护坡技术含义及优缺点？
