如果河流长期被污染,许多鱼类将难以正常繁衍。Rúguǒ héliú chángqī bèi wūrǎn, xǔduō yúlèi jiāng nányǐ zhèngcháng fányǎn.If the river remains polluted for a long time, many fish species will struggle to reproduce normally.
春天是许多小动物繁衍后代的季节。Chūntiān shì xǔduō xiǎo dòngwù fányǎn hòudài de jìjié.Spring is the season when many small animals raise their young.
这片森林很安静,小鸟们可以安心繁衍。Zhè piàn sēnlín hěn ānjìng, xiǎoniǎomen kěyǐ ānxīn fányǎn.This forest is quiet, so the little birds can breed in peace.