乃是

rén mín nǎi shì zhēn zhèng de yīng xióng

人民乃是真正的英雄。

The people are the true heroes.

tā de tǒng zhì nǎi shì tiān mìng

她的统治乃是天命。

Her rule was ordained by heaven.

měng liè pī pàn zhèng zhì rén wù nǎi shì xīn wén jiè cháng shì

猛烈批判政治人物乃是新闻界常事。

Bashing politicians is normal practice in the press.

qiàn zhài huán qián nǎi shì cháng lǐ

欠债还钱乃是常理。

To repay one's debts is common sense.