3 sentences

1. 守城士兵准备好了各种防御器械。

   shǒu​chéng shì​bīng zhǔn​bèi hǎo le gè zhǒng fáng​yù qì​xiè.

   The soldiers defending the city prepared all kinds of defensive equipment.

   Source: Dong Chinese Dictionary

2. 面对敌军的进攻，守城部队进行了顽强的抵抗。

   miàn​duì dí​jūn de jìn​gōng, shǒu​chéng bù​duì jìn​xíng le wán​qiáng de dǐ​kàng.

   Faced with the enemy's offensive, the defending troops put up stiff resistance.

   Source: Dong Chinese Dictionary

3. 由于主帅亲自率兵在城头防守，守城士兵们的士气都很高。

   yóu​yú zhǔ​shuài qīn​zì shuài bīng zài chéng​tóu fáng​shǒu, shǒu​chéng shì​bīng men de shì​qì dōu hěn gāo.

   Since the commander-in-chief personally led the troops to defend the city walls, the soldiers' morale was very high.

   Source: Dong Chinese Dictionary