4 sentences

1. 燕子在屋檐下搭了个小窝。

   yàn​zi zài wū​yán xià dā le gè xiǎo wō.

   Swallows built a nest under the eaves.

   Source: Dong Chinese Dictionary

2. 燕子被认为是春天的使者。

   yàn​zi bèi rèn​wéi shì chūn​tiān de shǐ​zhě.

   Swallows are considered messengers of spring.

   Source: Dong Chinese Dictionary

3. 燕子衔泥筑巢。

   yàn​zi xián ní zhù​cháo.

   Swallows carry mud in their beaks to build nests.

   Source: Dong Chinese Dictionary

4. 春天到了，小燕子从南方飞回来了。

   chūn​tiān dào le, xiǎo yàn​zi cóng nán​fāng fēi huí​lai le.

   Spring has arrived, and the swallows have flown back from the south.

   Source: Dong Chinese Dictionary