shy: implies a timid reserve and a shrinking from familiarity or contact with others: ~ in front of total strangers.  (timid一般的胆小，贬义不重，如he is timid by nature他生性胆小)


bash: implies a frightened or hesitant shyness characteristic of immaturity: the ~ boy rarely told us how he felt about anything.


diffident: stresses a distrust of one's own ability, opinion, or powers that causes hesitation in acting or speaking: felt ~ about raising an objection.


modest: suggests absence of undue confidence or conceit, or of boldness or self-assertion: very ~ about citing his achievements.   (self-assertion主断: 坚持自己的主张；bold大胆：这里表示轻率鲁莽)


coy: implies an assumed or affected shyness: don't be misled by her ~ demeanor.     (除表示忸怩作态，coy还表示含糊不愿意说: she is coy about her age她对年龄避而不谈 )


shy害羞: 指胆小矜持，不愿与人接触或熟悉，bash羞怯: 指害怕又害羞，由于不成熟，diffident羞怯、缺乏自信: 对自己的能力观点缺乏自信，modest谦虚: 不自满自夸、不自作主张或做事鲁莽，coy忸怩作态: 假装的害羞


记忆方法: 1) 首字母SBDMC排序成MSBCD没事不出动<==因为害羞

          2) 害羞的意思是不愿主动与人接触mean not inclined to be forward or obtrude oneself.首字母SBDMC排序成MSBCD没事不出动<==因为害羞   (forward向前，主动) (obtrude强行闯入或引人注意)