The study predicts the following changes in 40 years:

* a 20% drop in the use of Mandarin

* a 38% drop in the use of English

* a 17% increase in the use of Spanish

* a whopping 167% increase in the use of French

Hmm, hmm. Yeah, no. Don't learn French. If you already know English, learn Spanish. It's easier to learn, the grammar is gentler, it's widely used, people who speak it tend to be a little more relaxed when it gets mangled by the rest of us....

(Full disclosure: French is so close to a mother tongue for me it's not even funny, and is a mother tongue, along with English, for my daughter. Spanish is my third strongest language, much stronger than the few others I've learned and sort of lost.)