¡¡¡¡30. What does the author say about straight, horizontal bars painted across roads?
¡¡¡¡A) They cannot be applied successfully to traffic circles.
¡¡¡¡B) They tend to be ignored by drivers in a short period of time.
¡¡¡¡C) They are falling out of use in the United States.
¡¡¡¡D) They are applicable only on broad roads
¡¡¡¡ÇëÓÃÐÄÌå»áinitially Õâ¸ö´ÊµÄÄÚº£¬Æäʵ£¬ÄãÒ»¿´µ½Õâ¸ö´Ê£¬¾ÍÓ¦¸Ã׼ȷpredictºóÃæ¿ÉÄÜ»áÓп¼µã£¬¶øÇҿ϶¨»á³öÏÖbut, however, ultimately Ò»ÀàµÄתÕÛ¡¢¶Ô±È´Ê¡£´ð°¸B)¡£
¡¡¡¡µÚÎå²½£º·ÒëÎÄÕ»òÕßÓëÒëÎÄ(Èç¹ûÓÐ)¶ÔÕÕѧϰ
¡¡¡¡ÕâÒ»²½×î¾ßÓÐÌôÕ½ÐÔ£¬µ«¿ÉÒÔʹÄã¶ÔÓ¢ÎĵÄÀí½â¸ü׼ȷ£¬¿ÉÒÔÈÃÄã¸ü×ÔÓɵØÔÚÖÐÓ¢ÎÄÖ®¼ä³Û³Ò¡£
¡¡¡¡Í¬Ñ§ÃÇÔÚ½øÐг¬¾«¶Áʱ£¬¿ÉÒԲο¼ÒÔÉÏÎå¸ö²½Öè½øÐС£Èç¹û»¹ÓÐʲôÎÊÌ⣬»òÕßÎÒ˵µÄ²»µ±µÄµØ·½£¬»¶ÓÒ»ÆðÌÖÂÛ£¡ÎҵIJ©¿ÍµØÖ·Îª£º(xzding.diandian.net) ÁíÍâͬѧÃÇÒ²¿ÉÒÔµ½µãµãÓ¢Óﳬ¾«¶Áר°æ(bbs.diandian.net/index.asp?boardid=147)ºÍ¹ã´óÓ¢Óï°®ºÃÕßÒ»Æð¶Ô¡°³¬¾«¶Á¡±½øÐÐѧϰ¡¢ÑµÁ·¡¢ÌÖÂÛ£¬¹²Í¬Ìá¸ßÓ¢Óïˮƽ£¬Ó¢ÓïѧϰµÄµÀ·ÊÇÓÀÎÞÖ¹¾³µÄ£¡
¡¡¡¡×îºóÒýÓÃÒ»¸öÎÒÓëÒ»¸öÍøÉÏͬѧµÄ¶Ô»°À´½áÊøÕâÆªÎÄÕ£¬Ï£Íû¸÷λͬѧ¶¼ÄÜÔçÈÕÊÓÉî¿ÌµØÀí½âÓ¢ÓïΪһÖÖÏíÊÜ£¬²¢Ë³Àû¹¥¿ËÓ¢ÓïÕâ¸ö±¤ÀÝ¡£