牛仔裤的介绍:different usages of "一下" （with english please)

different usages of "一下" （with english please) is there are different version of psp? packing different types of products together;and Which of the following word sounds different from others “伦敦十景”的词组：10 different views of London The park has 25 different facilities of international standard. 改错：Every of his children goes to a different school. i was thinking of doing something different today what's the different between the education systerm of china and others ____ different kinds of ferilizers,the workers further improved their technique.