1989 Cantopop hit by Hong Kong band Beyond, written by 黄家驹 (Wong Ka Kui) as a tribute to his mother. Despite the title, it is a son-to-mother love song, not a romantic one: 是你多么温馨的目光 教我坚毅望着前路 ("your warm gaze taught me to face the road ahead with resolve"). A Mother's Day karaoke standard across the Chinese-speaking world.
usage
Read as a plain sentence, 真的爱你 just means "truly love you / I really love you". The song made it one of the most iconic four-character phrases in Cantopop.