T: 五月 S: 五月 [wu3 yue4] = May (the fifth month)

五月的第二個星期天是母親節。

五月的第二个星期天是母亲节。

wu3 yue4 de5 di4 er4 ge5 xing1 qi2 tian1 shi4 mu3 qin1 jie2.

The second Sunday in May is Mother's Day.

https://www.learnwitholiver.com/chinese/daily-sentence-520