My friend’s son wants to go to the USA and wants to learn English.  He is teaching me some Chinese and I am teaching him some English.  He doesn’t like math, but is pretty good at English.  I told him that he needs to learn math, not just English. In the USA, there are a lot of people who know how to speak English. He needs to know more than just that. He needs math.

So here is the problem I gave him . . .
If you stand on the sideline of a soccer field what is the spot on that line that gives you the widest net to shoot at? You can test some sample values using sines and cosines to estimate that spot, but there is only one spot on that sideline that is the best.  If you learn enough calculus to solve this problem, you will be strong. If you can’t do it, you will be weak.