"It describes the power needed to propel a bike against our everyday foes: gravity, weight, friction, wind resistance," he writes.
“它描述了推动自行车克服日常阻力——如引力、重量、摩擦力以及风阻——所需要的能量，”他这样写到。
2
Normal swells, known technically as gravity waves, are created by wind pushing the surface of the sea up and gravity then pulling it down, causing it to bounce.