The following contents are part of what I got from English vocabulary network yywords, but more contents are charged: excerpts from A [ei, e], an [an, en] art. 1. 1 (a piece, a book, a piece, etc. This is an English dictionary. /This is a simple task. That's an easy task. 2. Anything: A square has four sides. A square has four sides. Dogs are generally bigger than cats. Dogs are generally bigger than cats. We drink tea twice a day. We drink tea twice a day. /How much is this cloth one meter? How much is this cloth one meter? In a sense, you are right. In a sense, you are right. /A Mr Smith called just now. A man named Mr Smith called just now. Usage: 1 The indefinite article a/an should be added before singular countable nouns in general sense. Don't miss this indefinite article from Chinese habits. If you can't say: Her father is a famous poet. (a should be added after is a) 2. It cannot be used with demonstrative pronouns, possessive pronouns and possessive nouns. If you don't say my good friend, you can say. 3. In principle, you can't use indefinite articles before uncountable nouns, but if uncountable nouns are converted into countable nouns under certain circumstances, you can use indefinite articles before them. On the other hand, countable nouns can also be transformed into uncountable nouns under certain circumstances, and the indefinite articles in front of them also disappear: a complete complete collection of Lu Xun/a bottle of good wine/a successful person or thing 4. Before ordinal number, a (an) can indicate the increase of quantity or ordinal number: Do you want to read it for the third time? Do you want to see it a third time? Used with most to mean "very" and "very": this is a very interesting story. This is a very interesting story. 6. When used with adverbs quit and rather, a (an) is usually put in the back, but if the noun behind it is modified by adjectives, a (an) can be put before or after quit and rather: it's quite a busy day. It was quite a busy day. /He is rather stupid. He is a big fool. But it can't be said: he is quite stupid. Because there is no adjective before the noun, it is wrong. 7. When the words too, so, as, how are followed by "adjective+singular countable noun", the indefinite article a (an) should be placed between the adjective and singular countable noun: she is a kind girl who can't be refused. /He is not as honest as I thought. He is not as honest as I thought. 8. Indefinite articles can be used to indicate genera, that is, each of a genus can reflect the overall situation of the genus. A tiger [the tiger] can be dangerous. Note that indefinite articles cannot be used to express the characteristics of the whole category. In the following example, the cannot be replaced by a: the tiger is in danger of extinction. /Alexander Graham Bell invented the telephone in 1876. Alexander Graham Bell invented the telephone in 1876. Discrimination A (an), one: (1) Both can mean "one", and sometimes they can be interchanged: about a [one] about students attending the meeting. About 1 000 students attended the meeting. Mr Smith wants to see you. A man named Mr Smith wants to see you. (2) The difference between them: ① From the part of speech: a (an) is an indefinite article, which mainly indicates the category, that is, it emphasizes that the noun after it is something, not something else; When one means "one", it is a numeral, which mainly means quantity, that is, it emphasizes that there is one in quantity, not two or more. Give me a dictionary. Give me a dictionary. What I want is a dictionary, not a textbook, nor a novel. /Give me a dictionary. What I want here is a dictionary, not two or more dictionaries. ) because one is a numeral, it emphasizes the meaning of quantity, so when you want to emphasize quantity, compare quantity or answer how many questions, you should use one instead of a (an): he only has one pen and I have two. I want one box, not five. I want 1 box, not five boxes. /"How many friends do you have here?" "Only one." "How many friends do you have here?" "Only one." ③ In some expressions, both can be used, but their meanings are different: once at a time, at the same time/once; As a man, he is concerned about a person's personality. At the same time, in some expressions, both can be used. Although the meaning is the same, the expressions are different: on a hot summer afternoon (note the preposition on)/ on a hot summer afternoon (note the preposition on); One and a half hours (generally not one and a half hours)/one and a half hours; A minute or two (usually not a minute or two)/a minute or two abacus [5 abekes] (pl. Abacus, abacus; Abacus; Abacus; Abacus; Abacus give up. 1. The car was badly damaged and had to be completely scrapped. The car was badly damaged and had to be completely scrapped. The poor puppy was abandoned. The poor puppy was abandoned. 3. Give up: Due to lack of funds, this project has to be given up. Due to lack of funds, the project had to be abandoned. He fell into despair. He gave up on himself. Abandoning A ./ Abandoning n. [u] Abandoning usage 1. Abandoning A for B and abandoning A for B have different meanings: the former is to voluntarily abandon A for B, and the latter is to passively abandon A for B. He decided to give up medicine for literature. They gave up their land and let the invading army occupy it. They left their land and were occupied by the invading army. 2. There are articles in the collocation of abandoning cars, cities, villages, etc. In modern English, articles are usually not used for structural abandonment of ships. The idiom to is a preposition, so the verb is followed by gerund: they are addicted to alcohol. A similar structure is: concentrate on (doing) something. /devote yourself to (doing) sth. Let it (do) sth. Something. Give up; give up; cry heartily and dance heartily. Abbreviation: "Dr" is. /In this dictionary, "something" is the abbreviation of "something". This dictionary uses something as the abbreviation of something. Usage means the abbreviation of ",usually followed by the preposition for, and sometimes the preposition of:" GB "is the abbreviation of [of]" Great Britain ". GB is the abbreviation of Great Britain. ABC n . 1。 (often used with someone's letter) (Table): Does the boy know his ABC? Does the boy know letters? 2. [s] (often used with the) introduction, basic knowledge: learning the beginner's knowledge of swimming/an introductory book ◇ as easy as ABC is very easy [E5B ileti] n.1. Ability: My ability is inferior to his. My ability is inferior to his. I'm sure he has the ability to copy with this. I believe he is capable of handling this matter. 2. Ability, intelligence: A very capable person/this boy shows extraordinary talent in mathematics. The boy showed extraordinary mathematical ability. She did her best to do the work. She did the work to the best of her ability. Usage 1 He is capable of speaking English fluently. It is extremely important for news readers to be able to be heard clearly. A loud and clear voice is extremely important to news broadcasters. Occasionally, it can be followed by of doing the, but it is far less common than infinitive: I admit that he can finish the work quickly. I envy his quick work. 2. When expressing "ability" in the abstract sense, it is uncountable; When expressing different kinds of abilities, you can use the plural: listening, speaking, reading and writing abilities; When focusing on talent or ability, it can be countable or uncountable, and sometimes it can be used in the plural: everyone admires his ability. Everyone admires his talent. Note that the antonym of 1.able is impossible, but the antonym of ability is not impossible (the word does not exist in English), but impossible. 2.inability and dis- consist of negative prefixes in- and dis- respectively, but their meanings are different. The former means "can't" and "can't", while the latter means "can't" and "disabled". Capable ['knt] a. He is an able lawyer. He is a very capable lawyer. /He gave a very wonderful speech. He gave a wonderful speech. I can't come. I can't come. He can speak five languages. He can speak five languages. You should be able to get there in time. You should be able to get there in time. I haven't been able to get in touch with her. I have been unable to get in touch with her. Not knowing English, he didn't know what they wanted. As he doesn't know English, he doesn't know what they want. The comparative and superlative degree of 1 Usually more and more capable, but also more capable and competent, sometimes more capable and competent: you are more capable of doing this than I am. /She is the most capable person. She is the best person to deal with this problem. The infinitive in being able to do something is usually active, but generally not passive. For example, it can be said that he cannot be understood. But few people say that he can't be understood. It means that someone can do something, but in English, it is customary not to make someone do something. It can be changed so that someone can do something: I gave him detailed instructions so that he could find the house. I gave him a detailed explanation so that he could find the house. It would be more popular to help someone do something instead. ) 4. it means very capable or capable, and can be modified by very, extreme, etc. He is a very capable manager. He is a very capable manager. He is quiet [capable] of taking care of himself. He can take care of himself completely. Note that the antonym of unable is impossible, not disable, but a verb, meaning "disable" and "disable"; Disabled can also be used as an adjective, meaning "physical disability". Distinguishing energy, energy: seeing energy. Aboard 1 on (a ship, plane, car, etc.). ): He has already boarded the ship. /We travel on the same flight. Usage The ship itself can be used as a preposition, so the preposition on like go aboard on the ship is redundant. However, sometimes it can be followed by the preposition of: go of: go [come] on a board 2 [E5BC: d] ad. On a ship (plane, car, etc.). Board a ship (plane, car, etc.). Welcome to this plane (car, boat)! /The ship is ready to leave. Hop in. The ship is about to sail. Please board the plane. It's time to get on the boat. It's time to get on the bus (ship or plane). Usage: synonymous with on board as adverb: go board = go board to board (car or plane), get board the train = get board the train.