1. keep one’s eyes on the ball

释义：To keep oneself very focused on something. （自己保持警惕心，使自己集中精力）

e.g. I graduated in just three years because I was able to keep my eye on the ball and prioritize my studies above all else.

我只花了三年就毕业了，因为我能够集中精力，把学习放在首位。

e.g. Please keep your eyes on the ball and type, Miss Brown, stop looking out of the window!

布朗小姐，请你集中精力打字，不要往窗外看了！

e.g. A policeman has to keep his eyes on the ball against the possible danger all the time he's on duty.

警察在执勤时必须集中精力以防止可能发生的危险发生。

e.g. You must keep your eyes on the ball against possible dangers.

你必须保持警惕以防止可能的危险。

e.g. 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.

汤姆，你的销售量在过去半年里一直很低。你在这段时间里一共才卖了十七辆汽车，你还是集中注意力地工作。否则，你恐怕得另找工作了。

2. play ball with someone

释义：To cooperate with someone. （与某人合作）

e.g. If you play ball with me, I am not going to report you to the boss.

如果你和我合作，我就不会把你做的事情报告给老板听。

We need the Committee's approval for this scheme.Doyou think they'll play ball with us?

我们这项计划需要委员会的赞助。你认为他们会跟我们合作吗?

To my surprise, he refused to play ball with us.

令我吃惊的是，他不肯与我们合作。

e.g. Look, you play ball with me and tell me who your boss is, and maybe we can get the judge to take it easy on you.

你听着，你要是现在和我合作，告诉我你的老板是谁，这样也许我们可以让法官对你宽大处理。

3. have the ball on one’s feet

释义：To be in the best position to do something; to be in control. （有机会获得成功）

e.g. With his money and growing popularity he have the ball at his feet in the election.

以其财富及不断鹊起的声誉，他很可能在选举中获得成功。

I want to have the ball at my feet at the most crucial moment in a game — I want to be the hero.

我想在比赛的关键时刻获得成功，我想成为英雄。