frank: stresses lack of reticence in expressing oneself and connotes freedom from shyness, secretiveness, or considerations of tact or expedience : held ~ discussions on arms control.   （reticent不说话三缄其口，指不愿过多的说reluctance to speak out at length, especially about one's own affairs，特别是私事或一些需要注意的事情，没有贬义，不一定像taciturn一样表示性格孤僻不爱交往，如he is reticent about his plans他对自己的计划三缄其口）   (权宜expedience=expediency意思是用不太好的临时代替something used temporarily when the usual one is not available, 如the invitation to him is only an expediency邀请他来只是权宜之计)  （tact一般说成技巧，表示说话做事考虑场合以及是否合适，顾及别人的感受和影响implies delicate and considerate perception of what is fitting or appropriate under given circumstances，如use tact when inquiring about the divorce问及离婚时要注意技巧）  



candid: suggests expression marked by sincerity and honesty especially in offering unwelcome criticism or opinion: a ~ appraisal of her singing ability.


open: implies frankness and candor but suggests more artlessness than frank and less earnestness than candid: young children are ~ and artless in saying what they think.  （artless没有技巧，指说话做事不知道会给别人带来怎样的影响感受implies unawareness of the effect one is producing on others，和tactless同义，如例句中说小孩说话没有技巧，如gave an artless impromptu speech at the party宴会时作了不得体的即兴讲话）


plain: suggests outspokenness and freedom from affectation or subtlety in expression: very ~ about telling them to leave.  （subtle隐晦微妙难理解，如微小的区别或微妙的关系implies something difficult to perceive or understand, such as fine distinctions or minute relations，如we can use our eyes and facial expressions to communicate virtually every subtle nuance of emotions我们用眼睛和表情几乎可以表达出情感上的每一丝的微妙差异，nuance表示微小差异slight difference）   （affect假装做作不真诚，如his foreign accent is just an affectation他的外国口音只是假装出来的）


frank坦率: 指说话不保留害羞秘密技巧权宜，candid坦率: 也表示真诚诚实,但强烈暗示不受欢迎的批评或意见，open坦率直接: 坦率的程度介于前两词之间，plain直接: 说话直接(outspoken来自speak out,表示说话直接)不假装隐晦


记忆方法: 1）首字母FCOP想成Fat COP胖警察<==坦率


         2）坦率的意思是愿意说出感想mean showing willingness to tell what one feels or thinks.