needn't和don't need to分别用在什么时候
needn't \u548c don't need to \u6709\u4ec0\u4e48\u4e0d\u540c?need\u4f5c\u4e3a\u60c5\u6001\u52a8\u8bcd\u65f6\u5426\u5b9a\u5f62\u5f0f\u662fneedn't \uff0c\u540e\u9762\u53ea\u80fd\u8ddf\u52a8\u8bcd\u539f\u5f62\uff1bneed\u505a\u5b9e\u610f\u52a8\u8bcd\u65f6\u5426\u5b9a\u4e3adon't need 1\uff0cto\u540e\u9762\u7528\u52a8\u8bcd\u539f\u5f62\uff0c\u56e0\u4e3ato\u4e0d\u5b9a\u5f0f\u561b2\u540e\u9762\u53ef\u4ee5\u8ddf\u540d\u8bcd/\u4ee3\u8bcd\uff0c\u8868\u9700\u8981\u3002
\u8fd9\u9053\u9898\u5e94\u9009C
\u5206\u6790\uff1a1.need\u53ef\u4ee5\u4f5c\u5b9e\u610f\u52a8\u8bcd\uff0c\u4e3b\u8981\u7528\u6cd5\u6709\u4e24\u4e2a\uff1a
A need to do sth A\u9700\u8981\u53bb\u505a\u67d0\u4e8b(\u4e3b\u52a8)
A need doing sth A\u9700\u8981\u88ab......(\u88ab\u52a8)
\u4f8b:Mary needs to do her homework.
Your hair needs cutting.(=Your hair needs to be
cut)
\u6ce8:need\u4f5c\u5b9e\u610f\u52a8\u8bcd,\u65e2\u53ef\u4f5c\u53ca\u7269\u52a8\u8bcd,\u4e5f\u53ef\u4f5c\u4e0d\u53ca\u7269\u52a8\u8bcd.\u5426\u5b9a\u5f62\u5f0f\u4e3adon't/doesn't+need+\u5176\u4ed6
\u4f8b:I need it.(need\u4f5c\u53ca\u7269\u52a8\u8bcd)
2.need\u53ef\u4ee5\u4f5c\u60c5\u6001\u52a8\u8bcd,\u5176\u540e\u76f4\u63a5\u52a0\u52a8\u8bcd\u539f\u5f62,\u5426\u5b9a\u5f62\u5f0f\u4e3aneedn't/need not+\u52a8\u8bcd\u539f\u5f62
\u6240\u4ee5,\u672c\u9898\u4e2dA. needn't to go B. don't need go \u8fd9\u4e24\u4e2a\u9009\u9879\u4e0d\u7b26\u5408\u8bed\u6cd5.A\u9009\u9879\u5e94\u6539\u4e3aneedn't go ,B\u9009\u9879\u5e94\u6539\u4e3adon't need to go
就像needn't have done 和 didn't need to do 一样。
从用法上，前者是情态动词，后者是实义动词。
从意义上，前者暗示已经做了,有“本不需要”的意思，后者暗示还没有做，就是纯粹地“不需要”。
如：You needn't do the housework.(说话时你已经做了家务)
You don't need to do the housework.(说话时你尚未做家务)
needn't do：此处need为情态动词，含有”必要“的意思，仅用于否定或疑问句等
don't need to do：此处need为实义动词，意为：需要(某人/某物)，要
一般现在时中，通常可以替换使用。
但当 need + have + pp 时，表示：所做的事不必要
个人见解，仅供参考
绛旓細need鏃㈠彲鐢ㄤ綔鎯呮佸姩璇嶏紝涔熷彲鐢ㄤ綔瀹炰箟鍔ㄨ瘝銆俤on't need涓殑need鏄疄涔夊姩璇嶏紝needn't涓殑need鍒欐槸鎯呮佸姩璇嶃俷eedn't鏄儏鎬佸姩璇嶇殑鍚﹀畾寮忥紝don't need鏄姩璇嶇殑鍚﹀畾寮忋2銆佹剰鎬濊〃杈句笉鍚 don't need鏄笉闇瑕佺殑鎰忔濓紝姣旇緝濮斿銆傝宯eedn't鏄笉蹇呫傜洿鎺ユ嫆缁濄3銆佺敤娉曚笉鍚 涓鑸儏鎬佸姩璇嶄娇鐢ㄧ敤浜庣枒闂彞锛宯eed...
绛旓細1锛嶹e needn't have worried锛庡叾瀹炴垜浠笉蹇呰鎱屻2锛嶻ou needn't have mentioned it锛庝綘鏈潵涓嶅繀鎻愯捣杩欎欢浜嬨3锛嶻ou needn't have said that when he asked锛庡綋浠栭棶鐨勬椂鍊欙紝浣犲叾瀹炰笉蹇呰璇淬備笁銆乶eedn't鍚庣殑涓嶅畾寮忛棿鎴栦篃鑳界敤杩涜寮忔垨琚姩璇併備緥濡傦細1锛嶩e needn't be standing in the rain锛...
绛旓細needn't鍜宮ustn't鐨勫尯鍒负锛氭寚浠ｄ笉鍚屻佽娉曚笉鍚屻佷晶閲嶇偣涓嶅悓銆備竴銆佹寚浠ｄ笉鍚 1銆乶eedn't锛氫笉蹇呫2銆乵ustn't锛氱姝備簩銆佽娉曚笉鍚 1銆乶eedn't锛歯eed鐢ㄤ綔瀹炰箟鍔ㄨ瘝鐨勫熀鏈剰鎬濇槸缂哄皯鎬ュ垏闇瑕佺殑涓滆タ,寮鸿皟鎬ラ渶銆2銆乵ustn't锛歮ust琛ㄧず鎺ㄦ祴,鏆楀惈寰堝ぇ鐨勫彲鑳芥,涓鑸彧鐢ㄤ簬鑲畾鍙ヤ腑,鍦ㄥ惁瀹氬彞涓〃绀烘帹娴嬬敤can...
绛旓細He needn鈥檛 be told. 娌℃湁蹇呰鍛婅瘔浠栥侶e doesn鈥檛 need to be told. 涓嶉渶瑕佸憡璇変粬浜嗐傦紙鍗充粬宸茬煡閬撲簡锛塶eed浣滄儏鎬佸姩璇嶇殑鐢ㄦ硶锛歯eed鏈変綔鎯呮佸姩璇嶅拰瀹炰箟鍔ㄨ瘝涓ょ鐢ㄦ硶銆(1)need鐢ㄤ綔鎯呮佸姩璇嶆椂琛ㄢ滃繀椤汇佸繀瑕佲,鍚庣洿鎺ヨ窡鍔ㄨ瘝鍘熷瀷,need+do锛屽惁瀹歯eedn鈥檛 +do銆(2)need鏃犱汉绉般佹暟鐨勫彉鍖(绗笁浜...
绛旓細need鐨勫惁瀹氬舰寮忔湁涓ょ锛屽垎鍒槸needn鈥檛 have done涓巇idn鈥檛 need to do锛屼袱绉嶅舰寮忛渶瑕佸垎鎯呭舰浣跨敤銆1銆乶eedn鈥檛 have done鐨勭敤娉曘傚畠涓昏琛ㄧず鏌愪簨宸茬粡鍋氫簡锛屼絾鍚庢潵瑙夊緱娌″繀瑕佸幓鍋氾紝鍥犳甯稿惈鏈夎矗澶囨垨閬楁喚涔嬫剰锛岃瘧鎴愭眽璇氬父鏄滄湰鏉ヤ笉蹇??鈥濄傚锛欼 needn鈥檛 have cooked so much food.Nobody was ...
绛旓細1銆佺粨鏋勪笉鍚 need to be done锛氬疄鎰忓姩璇+浠嬭瘝+鍔╁姩璇+鍔ㄨ瘝鐜板湪鍒嗚瘝銆俷eed doing锛氬疄鎰忓姩璇+鍔ㄥ悕璇嶃2銆佺敤娉曚笉鍚 need to be done锛歯eed鐢ㄤ綔瀹炴剰鍔ㄨ瘝鏃讹紝鍙敤浜庤偗瀹氬彞銆佸惁瀹氬彞銆佺枒闂彞绛夊悇绉嶅彞寮忥紝鏈夊姩璇嶇殑鍏ㄩ儴鍙樺寲褰㈠紡鎺o be done銆俷eed doing锛歯eed鐢ㄤ綔瀹炴剰鍔ㄨ瘝鐨勫熀鏈剰鎬濇槸缂哄皯鎬ュ垏闇瑕佺殑涓滆タ...
绛旓細涓銆佹剰鎬濆強渚嬪彞 don't need鏄笉闇瑕佺殑鎰忔濓紱姣旇緝濮斿銆侷 don't need your help.鎴戜笉闇瑕佷綘鐨勫府鍔┿needn't鏄笉蹇咃紱鐩存帴鎷掔粷銆備簩銆丯eed鐢ㄦ硶 You needn't be in a hurry 浣犱笉鐢ㄦュ湪鑻卞紡鑻辫鍜岀編寮忚嫳璇篃鏈変笉鍚岀殑鐢ㄦ硶锛岃嫳寮忕洿鎺ュ惁瀹氾紝缇庡紡鍦ㄤ娇鐢ㄦ椂闇瑕佸姞鍔╄瘝銆傚湪鏃舵佷笂鐨勭敤閫斾篃涓嶅悓銆傞兘灞炰簬鍥哄畾...
绛旓細1銆佽娉曟ц川鐨勪笉鍚 needn't 鏄 need not 鐨勭缉鍐欏舰寮, 甯哥敤浜庡惁瀹氱浣垮彞涓, 琛ㄧず涓嶅繀瑕併傝宮ustn't 鏄 must not 鐨勭缉鍐欙紝琛ㄧず绂佹鎴栦笉鍏佽鐨勬剰鎬濄備緥鍙ワ細鈶燳ou needn't worry about it. 浣犱笉蹇呮媴蹇冭繖浠朵簨銆傗憽You mustn't smoke in public places. 浣犱笉鑳藉湪鍏叡鍦烘墍鍚哥儫銆2銆佸惈涔夌殑涓嶅悓 needn...
绛旓細needn't鏄儏鎬佸姩璇嶇殑鍚﹀畾寮忥紝don't need鏄姩璇嶇殑鍚﹀畾寮 need鏃㈠彲鐢ㄤ綔鎯呮佸姩璇嶏紝涔熷彲鐢ㄤ綔瀹炰箟鍔ㄨ瘝銆傚綋need浣滄儏鎬佸姩璇嶆椂锛屾剰鎬濇槸鈥滃繀瑕侊紝蹇呴』鈥濓紝涓昏鐢ㄤ簬鍚﹀畾鍙ワ紙needn't锛夊拰鐤戦棶鍙ワ紝绗笁浜虹О鍗曟暟涓嶅姞s锛岃繃鍘诲紡涓嶅姞ed锛涘綋need浣滃疄涔夊姩璇嶆椂锛屾剰鎬濇槸鈥滈渶瑕侊紝鎯宠鈥濓紝鍙敤浜庤偗瀹氬彞锛屽惁瀹氬彞锛坉on't ...
绛旓細don't need涓殑need鏄疄涔夊姩璇嶏紝needn't涓殑need鍒欐槸鎯呮佸姩璇嶃俷eedn't鏄儏鎬佸姩璇嶇殑鍚﹀畾寮忥紝don't need鏄姩璇嶇殑鍚﹀畾寮忥紝need鏃㈠彲鐢ㄤ綔鎯呮佸姩璇嶏紝涔熷彲鐢ㄤ綔瀹炰箟鍔ㄨ瘝銆侼eed鐨勭敤娉 need鏃㈠彲浠ヤ綔鎯呮佸姩璇嶏紝涔熷彲浠ヤ綔瀹炰箟鍔ㄨ瘝锛屼絾鏄畠浠殑鐢ㄦ硶涓嶅悓銆備綔涓烘儏鎬佸姩璇嶇殑need鐨勭敤娉曚笌鍏朵粬鎯呮佸姩璇峜an銆乵ay銆乵ust...
