1.adherence和adhesion 
   这两个词都是“粘附的”意思。
   adherence用于比喻的意思。例如:His adherence to the strict letter of the law. 
   adhesion是指物质上的。
   2. adjacent,adjoining,和contiguous 
   这些词都有next to“紧挨”的意思。
   adjacent“毗邻的,邻近的”,但它们可能并不相互直接接触。
   adjoining和contiguous指相互接触,通常之间有一个edge或boundary。
   3.admission和admittance 
   它们都有“the act of entering”的意思。
   但admission用于公共场合。
   The price of admission to the gallery is£5. 
   admittance不指公共场合,一般指私人的住所。
   4. adopted和adoptive
   adopted“收养的,过继的”
   an adopted son (daughter)养子(女);my adopted country
   y我所入籍的国家; adopted words外来语。
   adoptive“收养的”,我们说adoptive parents,但很少说adoptive child; 
   “采用的”,“假冒的”an adoptive courage假充勇敢。
   5.averse和adverse
   adverse“不利的,反对的”,用于事,不用于人。adverse weather conditions
   ; an adverse reaction.
   averse“嫌恶的,反对的,不乐意的”,常和“to”一起使用,而且用否定形式。
   6.advise和advice
   advise“劝告”(动词);advice“劝告”(名词)。
   7.affect和effect
   affect“影响”,它的第二个意思是“假装”,Though she affectes 
   indifference, I knew she was really very upset. 
   effect n.“结果”,“效力”。 “产生”,“导致”,它比“to 
   cause, to bring out”更为正式。His aim was to effect a radical change in the party structure.
   8.all ready和already 
   all ready意思是“completely prepared”
   already“已经”。He had already had his lunch.
   9.altogether和all together 
   altogether (in total)“总共”
   all together意思是“in a group”。如:We put the sheep all together in one field.这两个词还可以分开。We put all the sheep together in one field.
   10. allude和elude
   allude“暗指”,“暗示”,“(婉转)提到”。
   elude (to avoid or escape)“闪避,躲避”。如:to elude sib’s grasp逃脱,没有被逮住;to elude the law规避法律。The meaning eludes me.那个意义我摸不透。