火箭发动机的作用是瞬间的, 在适当的地方燃烧推进物生成 高速 粒子.A rocket motor's'bullets'are minute, high - speed particles produced by burning propellants in a suitable chamber.一种蓝色透明、有磁性的液体,由压缩气态氧获得,用作火箭推进物中的氧化剂.A two - component roc...
Yours truly was awoken by a shout: "Ahoy there!"鄙人被一声大喊惊醒：“喂！”Experts agreed that this was a truly sensational performance.专家们一致认为这的确是一场精彩绝伦的演出。The greenhouse effect is well and truly with us.我们完全处于温室效应中。...
What am I supposed to do with that petting zoo out there?我对着那些动物园宠物该干 什么 ?She was holding the cat in her arms and petting it tenderly.她抱着猫,温柔地抚摸着它.I ran to my favorite section : the petting section and started petting a ...