他突然神秘地出现了;我既没看到也没听到他进来。
It's universally acknowledged that success never comes out of thin air.人们公认,成功永远不会凭空产生。
When that happens, we pretty well prance around the house like we've somehow magically manufactured a day out of thin air.当这种情况发生时,我们就会在屋子里欢蹦乱跳,就好像凭空变出了一天似的。