坍塌了半边的天是用（）当做四根柱子撑起来的。
参考答案：东海神龟的四只脚
______ is surprising to us is that Tom, for _______ English was once boring, can speak English fluently as though he were a native speaker.
A．As; whom
B．What; whose
C．It; whose
D．What; whom
切痂植皮
