little,a Little,bit,a bit,lots of的区别,when while的区别

little 修饰不可数,few修饰可数名词复数 均含否定意义,表是少到几乎没有,a little修饰不可数,a few 修饰可数 均表少量,少数,bit单独不用做两次,a bit 只能接形容词副词原级或者比较级,a bit of,才可以用来修饰不可数名词.lots of可以与 a lot of互换使用,可修饰不可数名词和可数名词复数.此外,口语中还常用 a little bit 表有点
When和While的区别 ①when是at or during the time that,既指时间点,也可指一段时间,while是during the time that,只指一段时间,因此when引导的时间状语从句中的动词可以是终止性动词,也可以是延续性动词,而while从句中的动词必须是延续性动词.②when 说明从句的动作和主句的动作可以是同时,也可以是先后发生；while 则强调主句的动作在从句动作的发生的过程中或主从句两个动作同时发生.③由when引导的时间状语从句,主句用过去进行时,从句应用一般过去时；如果从句和主句的动作同时发生,两句都用过去进行时的时候,多用while引导,如：a.When the teacher came in,we were talking.当此句改变主从句的位置时,则为：While we were talking,the teacher came in.b.They were singing while we were dancing.④when和while 还可作并列连词.when表示“在那时”；while表示“而,却”,表对照关系.如：a.The children were running to move the bag of rice when they heard the sound of a motor bike.孩子们正要跑过去搬开那袋米,这时他们听到了摩托车的声音.b.He is strong while his brother is weak.他长得很结实,而他弟弟却很瘦弱.