Don't you think picnics are fine fun, Doctor Mcteague?你看野餐是不是有趣的娱乐, 麦克梯格医生?I have superintended cooking picnics.我曾经多次主持过这种生火的野餐.Do you go on picnics?你常去郊游 吗 ?...
气缸中的蒸汽膨胀并推动活塞向外运动.Steam in a cylinder expands to push a piston outward.当排气冲程开始时, 气缸被向上运动着的活塞刮掠.When the exhaust stroke starts, the cylinder is swept out by the upmoving piston.在发动机气缸里发生的动作,可以分为四个过程或冲程.The actions taking ...