槽钢弯曲矫正时，槽钢下部要用圆钢垫在两端，锤击点尽量靠近腹板，或在槽钢中垫上垫铁，以防（）变形。
A、翼板
B、垫板
C、腹板
D、垫铁
参考答案：A
______ the matter a secret , Jim told his father all that had happened .
A．More than keep
B．Rather than keep
C．Rather than keeping
D．Without having been kept
商业计划书类型有哪些？
