a. 关心的, 有关的, 参与的, 担心的相关词组: be concerned with be extremely concerned over sth be concerned in sth as far as I'm concerned be concerned about be concerned at

• 一般肯定句中不用far单独作状语，而用a long way.far组成的常用词组有：as far as. ①远至，一直到。如：He walked as far as the station. ②就……而言。如：As far as he was concerned these books were very good. ③只要。如：I can help you as far as I can. so for到目前为止。例：He is very well so far.
  
  ［误］ "Did you walk far?"
  
  "Yes，I walked far."
  
  ［正］ "Did you walk far?"
  
  "Yes, I walked a long way."
  
  ［析］ 一般肯定句中不用far单独作状语，而用a long way.far组成的常用词组有：as far as. ①远至，一直到。如：He walked as far as the station. ②就……而言。如：As far as he was concerned these books were very good. ③只要。如：I can help you as far as I can. so for到目前为止。例：He is very well so far.
  

enemy/friend/friendship/relative/relativity/relate/related/relation/relationship/relevant/concern/concerned
记忆：
1. enemy [ 5enimi ] ene-my ene想象为眼睛对眼睛；my, 我的；enemy, 眼对眼盯着我的人， n. 敌人, 仇敌 Can we avoid making enemies in our life? 我们一生能够不树敌吗？
2. friend [ frend ] fri-end 在同一个点上炒饭的人， n. 朋友 Our enemy’s friend may not be our enemy.敌人的朋友也许并不是我们的敌人。
3. friendly adj. 友好的 Jordan taught the boy in a friendly way.乔丹很友好地教那个男孩。
4. 加名词后缀-ship, friendship [ 5frendFip ] n. 友谊 Friendship is an important part in our life.友谊是我们人生的重要部分。
5. relate [ ri5leit ] re-late vt. 使联系，叙述, 讲 He often relates his glorious experiences to his students.他经常向他的学生讲述他过去的光辉岁月。
6. related [ ri5leitid ] adj. 有关系的 The book is related with the top scientists in the 20th century.这本书讲述20世纪的顶尖科学家们的故事。
7. relative [ 5relEtiv] n. 亲戚, 关系词, 相关物, 亲缘植物 adj. 相对的 Here we have no relatives. 我们在这儿没有亲戚。
8. relativity [ 7relE5tiviti ] n. 相对性，相对论 The world admired Albert Einstein for his theory of relativity 世人钦佩爱因斯坦的相对论。
9. relation [ ri5leiFEn ] A logical or natural association between two or more things; relevance of one to another; connection n. 关系, 联系, 叙述, 亲戚 There is no relation between the two points.这两点间没有联系。
10. relationship [ ri5leiFEnFip] The condition or fact of being related; connection or association. n.关系, 关联 What’s the relationship between the two speakers?这两个说话人之间是什么关系呢？
11. relevant [ 5relivEnt ] relev-ant adj. 有关的, 相应的 Let’s set out to collect the relevant information. 我们着手去搜集相关的信息吧。
12. concern [ kEn5sE:n ] con-cern cern, 音“涉”； concern vt. 涉及, 关系到 n.(利害)关系, 关心, 关注 It’s not his concern whether he will get rewards or not. 获不获奖，他无所谓。
13. concerned [ kEn5sE:nd ] adj. 关心的, 有关的 All the materials concerned have been checked twice.所有的相关材料都彼检查了两遍。
另类阅读：
The friend tries to help you while the enemy tries to hurt you. However, everything is relative. Friendship may break up into hatred and relations may become enemies.