English is the International language of Business. English is the primary language used when people from different countries meet to buy and sell, wholesale, or Business to Business.
Many businesses in Europe require their sales personnel to take The Cambridge English tests such as the BULATS, or the CAE as a before interviewing for a sales job.
English is ranked number two in the number of speakers in the world, with Mandarin Chinese being number 1. There were 1000 million English speakers in the world in 2012, as compared with 1151 million Mandarin Chinese speakers. French ranks number 11 with 166 million speakers. You need to know English to work in the business world.
A lot of these English speakers are not native speakers of English. If you do business with another country, say Spain or Germany, the language that they will have in common is English. That is not to say that there will not be misunderstandings. The German, English as a Second language speaker, will have a different accent than the Spanish speaker and it might be difficult for them to really communicate. But at least they will be speaking the same language.
English has many words from all the European Languages so it is possible that a Spanish speaker and a French speaker will already have a bit of vocabulary when they start to learn English.
Business English can be learned through a Business English course, that teaches the essential elements of how to conduct negotiations, giving a presentation, speaking about computers, SWOT and other topics. Check out the business English course by Skype and start speaking English to do Business.