单词	petcock
释义	petcock /ˈpɛtkɒk / noun A small valve positioned in the pipe of a steam boiler or cylinder of a steam engine for drainage or testing.They were fitted with a dial gauge, a vent port in the form of a petcock or counterweight, and a safety fuse.... This time I put a piece of tape over the petcock opening instead of using the screw on block off plate I had made to use on the first steps. Steam for ten minutes, then shut off the steam by either closing the petcock or dropping the weight gauge into place.
随便看	presentiate presentiation presentic presentient presentiment presentimental present imperfect presentism presentist presentive presently presentment presentness presentoir presentoire presentor present participle present perfect present stem present tense present-time present value present worth presepe presepio

英语词典包含243303条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。