「有口無心」，漢語成語，意思是嘴上說了，心裡可沒那樣想。指不是有心說的（say what one does not really mean），可以翻譯為「be sharp-tongued but not malicious」。
例句：
tā shì gè zhí lái zhí qù de rén，shuō huà yǒu kǒu wú xīn
他是個直來直去的人，說話有口無心。
He's a blunt man, often speaking sharply but meaning no harm.
tā zhè gè rén yǒu kǒu wú xīn nǐ shì liǎo jiě de
他這個人有口無心你是了解的。
You know what he is like. He says whatever enters his mind.
成語「半途而廢」出自《禮記·中庸》：「君子遵道而行，半途而廢，吾弗難已矣。」（有些品德不錯的人按照中庸之道去做，但是半途而廢，不能堅持下去，而我是絕不會停止的。）「半途而廢」指的就是做事中途放棄，不能堅持到底。在英語中，我們常用fall by the wayside或者give up halfway來形容一個人半途而廢，沒能完成某件事。
例句：
初學者們遇到困難就半途而廢。
Amateurs fall by the wayside when the going gets tough.
這項試驗一定要搞到底，不能半途而廢。
We must carry the experiment through to the end, not give up halfway.
愛屋及烏出處：《尚書大傳·大戰》：「愛人者，兼其屋上之烏。」
解釋：
因為愛一個人而連帶愛他屋上的烏鴉。比喻愛一個人而連帶地關心到與他有關的人或物。可以直譯為the love for somebody or something extends to everything related with it，或者直接用英語中現有的表達「love me, love my dog」表達。
例句：
她很喜歡法國時裝，愛屋及烏，也喜歡上了法國的文化。
She loves French fashion, and then extends this love to French culture.
禮尚往來的意思是禮注重相互往來和互惠，可以翻譯為etiquette requires reciprocity and mutual benefit。
「禮」即禮制；「尚」即崇尚、注重。有時也表示用對方對待自己的態度和方式去對待對方（one should treat the other party in the way the other party treats you），類似於「即以其人之道，還治其人之身」。
例子：
禮尚往來。往而不來，非禮也；來而不往，亦非禮也。
Etiquette values reciprocity and mutual benefit. It would go against it if someone who has received a gift does not reciprocate such goodwill.
厚積薄發的意思是充分地積累，少量地釋放，可以翻譯為accumulate as much as possible but to release a little at a time。其核心內涵是，凡事不可急於求成，應注重積累，充分準備，才能把事情做好（one should never seek quick results; rather, one should pay attention to accumulating knowledge and making full preparations before making advances）。
例句：
博觀而約取，厚積而薄發，吾告子止於此矣。
Read widely and absorb the best from the books you read; acquire deep learning and share it gradually – that is all I can tell you.
化幹戈為玉帛意思是消除仇怨，變戰爭為和平，變衝突為友好。「幹」「戈」是用於防禦和進攻的兩種武器（two weapons of war which were used for defense and attack respectively），借指戰爭、武力衝突；「玉」「帛」指玉器和束帛，是古代諸侯會盟、諸侯與天子朝聘時互贈的禮物（jades and silks which were gifts exchanged between feudal lords and tribute paid to monarchs），後來用於表示和平共處之意。
這句話可以翻譯為eliminate animosity in order to turn war into peace and turn conflicts into amity。
例句：
上天降災，使我兩君匪以玉帛相見，而以興戎。
Heaven has struck disaster, bringing our two sovereign lords to face each other, not with jades and silks, but with the instruments of war.