4 sentences

1. 候鸟飞往南方过冬。

   hòu​niǎo fēi​wǎng nán​fāng guò​dōng.

   Migratory birds fly south for the winter.

   Source: Dong Chinese Dictionary

2. 岸边有成群的候鸟在休息。

   àn biān yǒu chéng​qún de hòu​niǎo zài xiū​xi.

   Flocks of migratory birds are resting on the shore.

   Source: Dong Chinese Dictionary

3. 候鸟在迁徙过程中会飞越数千公里。

   hòu​niǎo zài qiān​xǐ guò​chéng zhōng huì fēi​yuè shù​qiān gōng​lǐ.

   Migratory birds fly over thousands of kilometers during their migration.

   Source: Dong Chinese Dictionary

4. 每年秋天，成千上万的候鸟会向南迁徙。

   měi nián qiū​tiān, chéng​qiān​shàng​wàn de hòu​niǎo huì xiàng nán qiān​xǐ.

   Every autumn, thousands of migratory birds migrate south.

   Source: Dong Chinese Dictionary