一：食言而肥是指说话不算数，却仍然得到了好处的情况。这个成语的意思是指一个人说了一些不负责任的话，但却因为这些话而受益。通常用来形容那些口出狂言、行动不负责任的人。

英文解释：To eat one's words and grow fat means to make promises that one cannot keep, but still benefit from them. This idiom describes a situation where a person benefits from their irresponsible words. It is usually used to describe those who make empty promises and do not take responsibility for their actions.

二：怎么读（音标）：shí yán ér féi （shí yán ér féi）

三：用法：通常用来形容那些说话不算数、行为不负责任的人。也可以用来形容某种情况下，一个人因为说了一些虚假的话而得到了好处。

四：例句1-5句且中英对照：

1. 他答应给我帮忙，但最后却食言而肥，什么都没做。（He promised to help me, but in the end he ate his words and benefited from it, doing nothing at all.）

2. 这个政客总是在竞选时大肆承诺，但上任后却食言而肥。（This politician always makes grand promises during the election, but after taking office he eats his words and benefits from it.）

3. 他说过要给我一份工作，但后来又反悔了，真是食言而肥。（He promised to give me a job, but later he changed his mind. He really ate his words and benefited from it.）

4. 不要轻易相信那些口出狂言的人，他们可能只是想食言而肥。（Don't easily believe those who make empty promises, they may just want to eat their words and benefit from it.）

5. 那个商人答应给我们更多的优惠，但最后却食言而肥，我们什么都没得到。（That businessman promised us more discounts, but in the end he ate his words and benefited from it, we got nothing at all.）

五：同义词及用法：食言而肥与“说话不算数”、“兑现不了承诺”等意思相近。

六：编辑总结：食言而肥是一个形象生动的成语，用来形容那些说话不算数、行为不负责任的人。它提醒我们要谨慎选择自己的言行，并且要对自己的承诺负责。同时也告诫我们不要轻易相信那些口出狂言的人。