T: 小聲 S: 小声 [xiao3 sheng1] = 1. in whispers, in low voice or volume 2. undertone

小聲點，你會把孩子們吵醒！

小声点，你会把孩子们吵醒！

xiao3 sheng1 dian3, ni3 hui4 ba3 hai2 zi5 men5 chao3 xing3!

Be quiet, you'll wake up the kids!

https://www.learnwitholiver.com/chinese/daily-sentence-2924