基本解釋[土木建築工程]下泄琯線英漢例句權威例句What could have been the highlight of the line-up of politicians, Congressman Paul Ryan, turned out to be a letdown.FORBES: At National Review Institute Gathering Conservatives Yell Stop. But Are Voters Listening?letdown line更多例句詞組短語短語letdown line isolation valve 下泄琯線隔離閥letdown line更多詞組專業(yè)釋義土木建築工程下泄琯線