Although Chinese language is probably the most used language in the world given the fact that Chinese population reaches over 1,5 mld people, English language is not less powerful and I think every average educated person should know it. At least the basics.
It's not true that Chinese is the most used language in the world. It is very hard to estimate, of course, because you need to calculate it for all countries in the world. Wikipedia shows that there are 1.10 billion speakers of Mandarin, while there are 1.12 billion speakers of English. This is including native speakers and those who learned the languages later. If you only count native speakers, then English is in 3rd place. Spanish is in 2nd place and Mandarin is in 1st. Since Chinese is really only spoken in one country and a few other territories that China doesn't consider countries, that makes it less significant. Bengali is the 9th most spoken language in the world, for example, but it's only spoken in one very small region, so it is not so influential.