重写句子：Not until he crossed the line and felt the tape snap against his chest did Johnson know he had won the race.(loose sentence)
Johnson did not know he had won the race until he crossed the line and felt the tape snap against his chest.
暂无解析
无阻尼单自由度体系自由振动的振幅不仅与动力特性有关，还与初位移和__________有关。
紊流的剪应力由粘性剪应力和_____两部分组成
土的粘聚力是土粒间的胶结作用、结合水膜以及分子引力作用等形成，土粒愈粗大，粘聚力愈____。
当堰顶厚度与堰上水头的比值满足时，这种堰称为_____。
普通完全井的出水量【】
