要当飞行员必须达到体格上的某些标准.To be a pilot, one must meet certain physical standards.要参军必须达到一定的体格上标准.To join the army, one must meet certain physical standards....
He is vacuuming a rug in the sitting room.他在起居室里用吸尘器打扫地毯.L am vacuuming the floor now and have several shirts to iron.我正在用真空吸尘器清理地板,还有好几件衬衫要熨.But a wide - open floor adds only a few seconds the vacuuming chore.但是,广泛的开放式购...