里论外几-
about 1
/ əˈbaut; əˋbaʊt/ adv
(also esp US around) a little more or less than; a little before or after; approximately 比...稍多或稍少; 在...稍前或稍后; 大约; 左右: It costs about 10. 这需10英镑左右. * He"s about the same height as you. 他大约像你那麽高. * She drove for about ten miles. 她开车行驶了大约十英里. * They waited for about an hour. 他们等了大约一个小时.
(infml 口) nearly 将近: I"m (just) about ready. 我（就）快准备好了.
(infml 口) (in understatements 用於含蓄的言语): I"ve had just about enough, ie quite enough. 我已经差不多够了（十分够了）. * He"s been promoted, and about time too, ie it ought to have happened earlier. 他获提升了, 也差不多到时候了（早就该提升了）.
(idm 习语) that"s about `it/the `size of it (infml 口) that is how I see it or assess it 大致如此[大小差不多]（据我所看到或估计到的）. about 2
/ əˈbaut; əˋbaʊt/ adv part (in senses 1, 2 and 3 esp Brit; in these senses also, esp US, around1、2、3义尤用於英式英语; 这些词义, 尤於美式英语, 也可用around)
(a) (indicating movement) here and there, in many directions; all around （表示动向）到处, 各处, 处处: The children were rushing a`bout. 孩子们到处乱闯. * The boys were climbing about on the rocks. 男孩子都在岩石上乱爬呢. (b) (indicating position) here and there (in a place) （表示位置）（在某一地方）到处; 各处: books lying about on the `floor 散置地上的书 * people sitting about on the `grass 在草地上各处坐着的人们.
in circulation; moving around 在传播中; 在流动中; 在周围活动: There was nobody a`bout, ie Nobody was to be seen. 周围没有人. * There"s a lot of `flu about, ie Many people have flu. 有许多人患流感. * He"ll soon be a`bout again, eg after an illness. 他不久就又能四处走动了（如病愈后）.
somewhere near; not far off 附近; 不远: She"s `somewhere about. 她就在附近.
facing around 向后转: put the ship a`bout, ie so as to face in the opposite direction 使船掉头（转成相反的方向） * It"s the wrong way a`bout. 刚好相反了. * A,bout `turn! ie Turn to face the opposite way (as a military command). 向后转! （军事口令）.
# a,bout-`turn (US a,bout-`face) n
1 turn made so as to face the opposite direction 向后转.
2 (fig 比喻) complete change of opinion, policy, etc 意见、 政策等完全改变: These new measures indicate an about-turn in government policy. 这些新措施表明政府的政策彻底改变了. about 3
/ əˈbaut; əˋbaʊt/ prep (in senses 1, 2 and 5 US around; Brit also around in these senses 1、2、5义, 美式英语用around; 这些词义, 英式英语也可用around)
(a) (indicating movement) here and there in (a place); in many directions in （表示动向）在...到处, 在...各处: walking about the town 在城里到处走 * travelling about the world 环游世界 * Look a`bout you. 看看你的周围. (b) (indicating position, state, etc) here and there in (a place); at points throughout （表示位置、 状况等）在（某地）到处; 在所有各点: papers strewn about the room 散置於室内各处的文件.
near to (a place); not far off from 在...附近; 离...不远: She"s somewhere about the place. 她就在附近. * I dropped the key somewhere about here. 我把钥匙掉在这儿附近了.
on the subject of (sb/sth); in connection with; concerning or regarding 关於; 对於; 有关: a book about flowers 关於花卉的书 * Tell me about it. 把这件事告诉我. * What is he so angry about? 他对什麽事这麽生气? * He is careless about his personal appearance. 他对自己的仪表毫不在意. =>Usage 见所附用法.
concerned or occupied with (sth) 从事於; 忙於: And while you"re a`bout it..., ie while you"re doing that... 在你做那件事的时候... * Mind what you"re about, ie Be careful. 注意你正在做的事（小心）.
at a time near to; at approximately 将近...的时候; 大约在...: He arrived (at) about ten o"clock. 他大约（在）十点钟到的.
(idm 习语) be about to do sth intend to do sth immediately; be on the point of doing sth 即将; 正要: As I was about to say when you interrupted me... 我正要说的时候, 你插嘴了... * We"re about to start. 我们即将动身. * I"m not about to admit defeat, ie I have no intention of doing so. 我还不想认输. how/what about...? (a) (used when asking for information or to get sb"s opinion 用以询问消息或徵求意见): What about his qualifications (ie Is he qualified) for the job? 他有资格做这件工作吗? (b) (used when making a suggestion 用以提出建议): How about going to France for our holidays? 咱们到法国去度假好吗?
NOTE ON USAGE 用法: Both about and on can mean `on the subject of". *about和on均意为‘关於". A book, film or lecture on Chinese art, education or prehistory suggests a serious, academic presentation. 在关於中国的艺术、 教育或史前时期的书、 电影或演讲中, 用on意味着具有严肃的学术性的内容. A book, discussion or TV programme about China, schools or dinosaurs is of more general interest and more informal. 在关於中国、 学校或恐龙的书、 讨论会或电视节目中, 用about则更具一般性和通俗性.
gitcloud-
看它的词性，大多数时候它作介词，不过还可以做名词，副词，形容词
当然，还有固定词组搭配
以下是做介词时
prep.
1. 在…周围，围绕着：例句: The young girl had a gold chain about her neck.
那位少女脖子上戴着一串金项链。
2. 到处，在(一定范围内的)各处，在…各方：例句: The children had left their toys lying about the room.
孩子们把玩具扔得满屋都是。
3. (空间上)在…附近，靠近；在…周围：例句: The streets about the castle are full of places of historic interest.
城堡周围的街道上净是名胜古迹。
4. 在一定的地方(或范围之内)的某处：例句: Miss Mary does not appear to be about the house, so I presume she has gone out.
玛丽小姐看来不在家里，我估计她是出去了。
5. 在指明的范围内从一处到另一处：例句: The nature of his business enables him to get about the world a good deal.
他业务的性质使他能经常到世界各地去跑。
6. 在…身上，在…身边：例句: I suddenly realised that I had no money about me.
我忽然想起来身上没钱。
7. 有关某物(或某景)的特点(或外观方面)，有关一个人的性格(或外貌)方面：例句: There was something about her that I did not like.
她身上有些东西我不喜欢。
8. 在(人体的)…部位：例句: He beat her about the head.
他打在她的头部。
9. (时间上)在…前后，在…左右，约略，大约，大概；相近，相似，近似：例句: The snow began about midnight.
午夜前后开始下雪。
10. 与…有关，关于，涉及，对于，在…方面；论及：例句: a book about the World War Ⅱ
一本关于第二次世界大战的书
11. 与…有关系，与…有联系：例句: Father doesn"t worry much about me.
父亲不太为我担心。
12. 注意；从事于…(某种活动)；做，干：例句: I don"t like to be interrupted when I am about an important piece of work.
我在做一件重要的工作时，不喜欢有人打扰。
13. 刚要…；即将…之时，正要…的时候，正准备(后接动词不定式)：例句: I am about to say something.
我刚要说某事。
其余词性可以查字典