全世界都知道我爱你
[quán shì jiè dōu zhī dào wŏ ài nĭ]
The direct translation means 'the whole world knows I love you'. It shows the speaker's loud and open declaration of their feelings for another person, expressing love without reservation. However, depending on context, this can also carry undertones of exasperation and hopelessness if met by indifference.