To keep one's eye on the ball这个常用语原先是来自球类运动,如网球、高尔夫球、垒球等。你一定要把眼睛看准了才能打到这些球。下面这个垒球运动员说的话就能说明问题:
"We were playing Chicago there and the crowd was yelling and booing and waving handkerchiefs to distract us. But I kept my eye on the ball, swung as hard as I could and hit a home run. That Chicago crowd sure quieted down as I jogged around the bases."
可是现在to keep one's eye on the ball已经可以应用到一般的事物上了。让我们来举一个汽车推销员的例子吧。这个人家里有些事不顺心,使他在工作时很分散精力。于是,他的老板就把他叫到办公室去对他说:
"Tom, your sales record is way down the past six months. You've only sold 17 cars all this time. You'd better start keeping your eye on the ball, or you'll find yourself looking for another job."