American English and British English differ from each other. There are differences between the two in the phonetic values of certain vowels, particularly in the single and compound vowels of the kind of British English known as Received Pronunciation, the kind taught to Eliza Doolittle by Professor Higgins in Bernard Shaw's play Pygmalion, and sometimes made fun of in the expression How now, brown cow. Different phonetic choices are also apparent, as for examples in bath, either, clerk, fertile, and in the pronunciation of z (as zee in America and as zed in Britain). Stress patterns differ, as do the number of syllables in words such as medicine, necessary, laboratory, and missionary, and the intonation patterns for sentences. Vocabulary differs between American and British English as a result of certain cultural differences, and the parallel development of certain inventions, for example, the automobile and the railroad. Vocabulary differences are seen in the following American words (the British equivalent is in brackets): moccasin, prairie, peanuts, clerk (shop assistant), homely (plain), letter carrier or mailman (postman), railroad (railway), hood (bonnet), trunk (boot), TV (telly), taxed (rates), subway (underground). The most subtle difference of all are the syntactic ones. British English has a preference for the use of have as a full verb in "Haven't you any?" as opposed to an American preference for "Don't you have any?" Likewise, the use of those and ones together in "Give me those ones" is a British usage, just as the tendency to add prepositions to verbs as in visit with and call up is an American usage.