【成語來源】?

to feel just like a fish in water
如魚得水

In the late Eastern Han Dynasty, the country was in confusion.
東漢末年，天下大亂。

In order to reunite the country, Liu Bei paid a visit to Zhu Geliang who had hidden himself in the countryside.
劉備為統(tǒng)一天下，特意拜訪隱居的諸葛亮尋求幫助。

He went there twice but didn't see Zhu Geliang. Then the third time he finally met him.
他連去了兩次都沒見到諸葛亮，第三次才見到了他。

Liu Bei explained why he came and explained his noble ambition to Zhu Geliang.Zhu Geliang also proposed some very good strategies.
劉備說明來意，并暢談了自己的宏圖大志。諸葛亮也提出了周詳?shù)膽?zhàn)略方針。

After listening, Liu Bei was so happy, he appointed Zhu Geliang as his military advisor.He said: "Zhu Geliang to me is as water is to fish."
劉備聽后大喜，于是立諸葛亮為軍師。他說：“我劉備有了諸葛亮，就好像魚兒有了水一樣。”

With the assistance of Zhu Geliang, Liu Bei's power expanded rapidly, and finally he realized his goal.
劉備在諸葛亮的幫助下，勢(shì)力不斷擴(kuò)大，最終實(shí)現(xiàn)了目標(biāo)。

Nowadays, this phrase is often used to describe the person who stays in the environment which suits him/her perfectly, or someone who is very adept at using the suitable or right methods.
如今,這個(gè)短語常常被用來形容一個(gè)人處在完全適合自己的環(huán)境中，或者一個(gè)人能夠熟練地應(yīng)用合適的或正確的方法。

【文化鏈接】

“如魚得水”用英文可以表達(dá)為“feel just like a fish in water”，我們來看一個(gè)例句：

I've wanted to study at Beijing University my whole life. I also love the culture and the weather in Beijing. I feel just like a fish in water.
去北京大學(xué)學(xué)習(xí)是我一生的夢(mèng)想。我還喜歡北京的文化氣氛和天氣。我在北京簡(jiǎn)直就是如魚得水。