单项选择题
A．Clerk and customer. B．Doctor and patient. C．Policeman and motorist. D．Lawyer and client.
A．every tenth day B．every seventh day C．every fifth day D．either A or E
A．everyone can find familiar words in any other languages B．English was an immigrant language to the New World C．The necessity of communication gives rise to word borrowing D．Columbus successfully made the people understand each other