When two armies oppose one another, those who can fight should fight, those who can't fight should guard, those who can't guard should flee, those who can't flee should surrender, and those who can't surrender should die.
Mandarin
他后悔对敌人出卖了他的国家。
他後悔對敵人出賣了他的國家。
tā hòu huǐ duì dí rén chū mài le tā de guó jiā 。
He repented having betrayed his country to the enemy.
Facing the vigorous attack from their opponent, they are at a loss.
Examples (Wiktionary)
Mandarin
其领导人民对敌斗争的策略，必须是利用一切可以利用的公开合法的法律、命令和社会习惯所许可的范围，从有理、有利、有节的观点出发，一步一步地和稳扎稳打地去进行，决不是大唤大叫和横冲直撞的办法所能成功的。
其領導人民對敵鬥爭的策略，必須是利用一切可以利用的公開合法的法律、命令和社會習慣所許可的範圍，從有理、有利、有節的觀點出發，一步一步地和穩紮穩打地去進行，決不是大喚大叫和橫衝直撞的辦法所能成功的。
qí lǐng dǎo rén mín duì dí dòu zhēng de cè lüè ， bì xū shì lì yòng yī qiè kě yǐ lì yòng de gōng kāi hé fǎ de fǎ lǜ ， mìng lìng hé shè huì xí guàn suǒ xǔ kě de fàn wéi ， cóng yǒu lǐ ， yǒu lì ， yǒu jié de guān diǎn chū fā ， yī bù yī bù de hé wěn zhā wěn dǎ de qù jìn xíng ， jué bù shì dà huàn dà jiào hé héng chōng zhí zhuàng de bàn fǎ suǒ néng chéng gōng de ．
In leading the people in struggle against the enemy, the Party must adopt the tactics of advancing step by step slowly and surely, keeping to the principle of waging struggles on just grounds, to our advantage, and with restraint, and making use of such open forms of activity as are permitted by law, decree and social custom; empty clamour and reckless action can never lead to success.
Mandarin
将敌军对我军的战略上的分进合击，改为我军对敌军的战役或战斗上的分进合击。
將敵軍對我軍的戰略上的分進合擊，改為我軍對敵軍的戰役或戰鬥上的分進合擊。
jiāng dí jūn duì wǒ jūn de zhàn lüè shàng de fēn jìn hé jī ， gǎi wéi wǒ jūn duì dí jūn de zhàn yì huò zhàn dòu shàng de fēn jìn hé jī ．
We can change the converging attack directed by the enemy against us on the plane of strategy into converging attacks directed by us against the enemy on the plane of campaigns and battles.
Mandarin
大敌当前，他们要联合工农反对敌人；工农觉悟，他们又联合敌人反对工农。
大敵當前，他們要聯合工農反對敵人；工農覺悟，他們又聯合敵人反對工農。
dà dí dāng qián ， tā men yào lián hé gōng nóng fǎn duì dí rén ； gōng nóng jué wù ， tā men yòu lián hé dí rén fǎn duì gōng nóng ．
When confronted by a formidable enemy, they united with the workers and peasants against the enemy, but when the workers and peasants awakened, they turned round to unite with the enemy against the workers and peasants.