1) India has been an independent country since/for ... 1945; the end of World War II; the last five decades; more than

1) India has been an independent country since 1945;India has been an independent country since the end of World War II;India has been an independent country for the last five decades;India has been an independent country for more than 50 years.2) Our company has sold 50 types of new goods since 1993;Our company has sold 50 types of new goods since last year;Our company has sold 50 types of new goods for six months;Our company has sold 50 types of new goods for twenty-four weeks;Our company has sold 50 types of new goods since the beginning of the year 2001;Our company has sold 50 types of new goods since the new machines were bought; Our company has sold 50 types of new goods for two years.