頭發(fā)生長(zhǎng)的速度可能極其緩慢。The rate at which hair grows can be agonisingly slow.在我生長(zhǎng)的倫敦，四周全是轟炸后的斷壁殘?jiān)?。In London, where I grew up, we were surrounded by bomb sites.象牙磨損的速度快于生長(zhǎng)的速度。Elephants wear the tusk down faster than they can grow i...