Many a slip (many things fall) between the cup and the lip.
酒杯来到嘴唇边,得饮与否未可知;物未到手前,未能算己有;凡事难以十拿九稳。
They had to work inside the ship, cutting away old metal, fixing new metal plates, drilling holes, laying electrical and phone wires and fixing new pipes for water and steam.