Spanish, French and German, which is more widely used, which is more promising, and which fields are concentrated in?

French and Spanish are widely used and have more development prospects. French is mainly used in France, Belgium, Switzerland, Canada and half of African countries. Spanish is mainly used in Spain, South America and some African countries. German has little meaning. It is mainly used in Germany, Austria and Switzerland. People in these countries are of good quality, and most of them can speak English, so German is of little use.