答案:Free convertibility is not universal. Many countries place some restrictions on their residents’ ability to convert the domestic currency into a foreign currency (a policy of external convertibility). Restrictions range from the relatively minor (such as restricting the amount of foreign currency they may take with them out of the country on trips) to the major (such as restricting domestic businesses’ ability to take foreign currency out of the country). External convertibility restrictions can limit domestic companies’ ability to invest abroad, but they present few problems for foreign companies wishing to do business in that country. For example, even if the Japanese government tightly controlled the ability of its residents to convert the yen into U.S. dollars, all U.S. businesses with deposits in Japanese banks may at any time convert all their yen into dollars and take them out of the country. Thus, a U.S. company with a subsidiary in Japan is assured that it will be able to convert the profits from its Japanese operation into dollars and take them out of the country.