问答题 The earliest English dictionaries for foreign learners were an outgrowth of English language teaching by British educators in Japan. The New Method English Dictionary (1935) was the first dictionary for foreign learners. Oxford editions of the Advanced Learner’s Dictionary (OALD) were not seriously challenged until the appearance in 1978 of the Longman Dictionary of Contemporary English (LDOCE) . LDOCE was an innovative work in a number of ways. With a completely modern approach to vocabulary selection, containing many current idioms, slang, and colloquialisms, LDOCE was well received by learners and teachers alike. It gave much more attention to American English than the contemporary e-dition of OALD. It simplified the presentation of grammar, employed a defining vocabulary limited to about 2, 000 words, and was printed in an attractive, readable style. Suddenly the door was open for other ESL dictionaries. It was not long before others seized upon the opportunity to compete in this growing market. Following the publication of LDOCE in 1978, the rapid development of linguistic corpora resulted in two major new ESL dictionaries—Collins Cobuild English Language Dictionary in 1987 and Cambridge International Dictionary of English in 1995 to join OALD and LDOCE ESL lexicography is an area in which the British have always been far ahead of America because historically the teaching of English throughout world was largely a product of British colonialism and the role of British missionaries to spread the word of the English Bible. Both in theory and practice, ESL lexicography had been led by British and other European scholars of the English language. The last few years, however, have seen a dramatic change in the North American market. In the past, Oxford and Longman produced ESL dictionaries for the American market, supposedly in American English, but both were small in size and were obviously closely based on their British progenitors. As far as the coverage of many common American usages went, they were grossly inadequate. The publication of the Longman Dictionary of American English (2nd, 1997) marks a turning point in the history of ESL lexicography in America, as this is the first corpus-based, soundly edited ESL dictionary giving extensive coverage of American English. It was followed in 1998 by the Oxford American Wordpower Dictionary, and in late 1999 by the Cambridge Dictionary of American English, which was based on a large corpus of current American English. These three, all published under the imprints of British publishers but edited by American lexicographers, have raised the quality of ESL lexicography in America to a higher level. However, as these three dictionaries have been joined by a raft of other dictionaries , none of them is corpus-based, and therefore not nearly as reliable in representing actual usage , although they are not without their individual merits. Now that American publishers have discovered there is an ESL market for American English, we can expect a continuing stream of dictionaries, but they have a long way to go before they will be able to match the British-made ESL dictionaries, especially at the advanced levels.