a / an 為不定冠詞，用在非特定的名詞前。an用在母音字首的名詞前。He is a teacher. She is an assistant.the 為定冠詞，用在表限定，特定的名詞前。He is the teacher from the U.S.一些規則：1. a/an為不定冠詞，放在非特定的單數可數名詞前。Do you have a pen? 你有筆嗎？任何一支，沒有特定的。 He is an old man.2. 當一個單數可數名詞第一次被提到的時候要用a/an，再次提到的時候前面要用the。I saw a dog. The dog ran away.3.在there is / there are 後面的名詞不可加the。單數可數名詞前加a / an。所有名詞無論是單數或複數，在there is / there are 後面皆為不特定。There is a pen on the table.There were planes in the sky.4. 當提及在世界上唯一存在的事物時，前面要加theThe sky is blue. (The sun, the moon, the earth)5. 表達形容詞副詞的最高階superlative時，前面要加the。Paris is the most beautiful place I’ve ever been.He is the tallest student in my class.6. 在動物園zoo，花園garden，博物館museum，機構institute，公司company的名字前面要加the。The Ford Motor Company was founded by Henry Ford.7. 在飯店hotel/motel，劇院theater，橋bridge和建築物building的名字前要加the，但是在廳堂，醫院的名字前不加the。The Hilton Hotel is on Main Street.I was born in National Taiwan University Hospital.8. 姓氏後面加名詞時，前面要加theThe Everly Brothers were a famous musical duet.9. 在複數名字前加theThe Johnsons bought a new car last week.10. 在河流river，海洋ocean/sea，沙漠desert前要加the。The biggest ocean in the world is the Pacific.11. 在單獨的湖泊，山脈，島嶼，峽谷前不加冠詞a/an或the，但複數時要加the。Only a few people have climbed Mt. Everest.The Rocky Mountains are in the western United States.12. 在國家country，城市city，州state前不可加冠詞a/an或the，但是某些特定字組合成國家的名稱時，前面要加the。The capital of Taiwan is Taipei.There are fifty states in the United States. the Republic of China, the United Kingdom13. 在街道名稱street, avenue, road, boulevard前不可加the。Fifth Avenue is a famous street in New York.I live on Thomas Street.14. 複數名詞前不可加a/an。I have friends in Canada.15. 不可數名詞前不可加a/an。She drinks orange juice every day.16. 不可數名詞除非是特定，否則前面不可加theDo you often drink milk? Do you like the coffee I made?17. 在早上，下午，傍晚前要加the，但是晚上，中午，午夜前不加the。He always leaves home in the morning and goes home at night.in the morning, in the afternoon, in the evening at noon, at night, at midnight18. 在一些go的片語或複合字，名詞前面不加the。通常是一些地方你固定去的，比方說家裡，學校，教堂，都會去同一間。Do you go to church? go to bed, go to class, go to school, go to college, go to jail, go home.
a / an 為不定冠詞，用在非特定的名詞前。an用在母音字首的名詞前。He is a teacher. She is an assistant.the 為定冠詞，用在表限定，特定的名詞前。He is the teacher from the U.S.一些規則：1. a/an為不定冠詞，放在非特定的單數可數名詞前。Do you have a pen? 你有筆嗎？任何一支，沒有特定的。 He is an old man.2. 當一個單數可數名詞第一次被提到的時候要用a/an，再次提到的時候前面要用the。I saw a dog. The dog ran away.3.在there is / there are 後面的名詞不可加the。單數可數名詞前加a / an。所有名詞無論是單數或複數，在there is / there are 後面皆為不特定。There is a pen on the table.There were planes in the sky.4. 當提及在世界上唯一存在的事物時，前面要加theThe sky is blue. (The sun, the moon, the earth)5. 表達形容詞副詞的最高階superlative時，前面要加the。Paris is the most beautiful place I’ve ever been.He is the tallest student in my class.6. 在動物園zoo，花園garden，博物館museum，機構institute，公司company的名字前面要加the。The Ford Motor Company was founded by Henry Ford.7. 在飯店hotel/motel，劇院theater，橋bridge和建築物building的名字前要加the，但是在廳堂，醫院的名字前不加the。The Hilton Hotel is on Main Street.I was born in National Taiwan University Hospital.8. 姓氏後面加名詞時，前面要加theThe Everly Brothers were a famous musical duet.9. 在複數名字前加theThe Johnsons bought a new car last week.10. 在河流river，海洋ocean/sea，沙漠desert前要加the。The biggest ocean in the world is the Pacific.11. 在單獨的湖泊，山脈，島嶼，峽谷前不加冠詞a/an或the，但複數時要加the。Only a few people have climbed Mt. Everest.The Rocky Mountains are in the western United States.12. 在國家country，城市city，州state前不可加冠詞a/an或the，但是某些特定字組合成國家的名稱時，前面要加the。The capital of Taiwan is Taipei.There are fifty states in the United States. the Republic of China, the United Kingdom13. 在街道名稱street, avenue, road, boulevard前不可加the。Fifth Avenue is a famous street in New York.I live on Thomas Street.14. 複數名詞前不可加a/an。I have friends in Canada.15. 不可數名詞前不可加a/an。She drinks orange juice every day.16. 不可數名詞除非是特定，否則前面不可加theDo you often drink milk? Do you like the coffee I made?17. 在早上，下午，傍晚前要加the，但是晚上，中午，午夜前不加the。He always leaves home in the morning and goes home at night.in the morning, in the afternoon, in the evening at noon, at night, at midnight18. 在一些go的片語或複合字，名詞前面不加the。通常是一些地方你固定去的，比方說家裡，學校，教堂，都會去同一間。Do you go to church? go to bed, go to class, go to school, go to college, go to jail, go home.
記住特定的對立就可以了，特定就是獨一無二的 如太陽 月亮
希望可以幫到你