English is probably the most universally accepted international language in many areas, such as science. Also, many children already learn a second language, and those who don't normally don't because they struggle enough with English. Also, which language. A lack of teachers make many languages difficult to access, and those that are e.g. French, Spanish, German, Italian, are not as useful as some like Urdu or Mandarin, which are far more difficult and there would simply not be enough teachers for