The discovery that language can be a barrier   to communication is quickly made by all who travel, study, govern or sell. Whether the activity is tourism, research, government, policing or business, the lack of a common language can severely delay progress or can stop it altogether. Although communication problems of this kind must happen thousands of times each day, very few become public knowledge. Publicity comes only when a failure to communicate has major results, such as strikes, lost orders, legal problems or deadly accidents--even, at times, war. One reported example of communication failure took place in 1970, when several Americans ate a species of poisonous mushroom. No remedy was known, and two of the people died within days. A radio report of the case was heard by a chemist who knew of a treatment that had been successfully used in 1959 and published in 1963. Why had the American doctors not heard of it seven years later? Possibly because the report of the treatment had been published only in journals written in European languages other than English.   Several comparable cases have been reported. But isolated   examples do not give an impression of the size of the problem--something that can come only from studies of the use or avoidance of foreign-language materials and contacts in different communicative situations. In the English-speaking scientific world, for example, surveys of books and documents consulted in libraries and other information agencies have shown that very little foreign-language material is ever consulted. Library requests in the field of science and technology showed that only 13 percent were for foreign language journals. The language barrier presents itself entirely to firms who wish to market their products in other countries. British industry, in particular, has in recent decades often been criticized for its assumption   that foreign buyers will be happy to communicate in English, and that awareness of other languages is not therefore a matter to be considered first. In the 1960s, over two-thirds of British firms dealing with non-English-speaking customers were using English for outgoing letters; many had their sales language only in English; and as many as 40 percent employed no one who was able to communicate in the customer's languages. A similar problem was identified in other English-speaking countries, especially the USA, Australia and New Zealand. And non-English speaking countries were by no means free from the same problem--although the widespread use of English as an alternative   language made them a bit more able to communicate with other countries. The criticism and publicity given to this problem since the 1960s seems to have greatly improved the situation. Industrial training projects have promoted an increase in language and cultural awareness. Many firms now have their own translation services. Some firms run part-time language courses in the languages of the countries with which they are most involved; some produce their own technical glossaries  , to ensure consistency   when material is being translated. It is now much more readily accepted that marketing efforts can be delayed, damaged or ruined by a failure to take the language needs of the customer into consideration. Firms of English-speaking countries use English only when marketing their products because   _  .
English is their official language they don't know their products will be sold abroad people in their countries don't know other languages they think foreign customers will be happy when English is used