Never frown, even when you are sad, because you never know who is falling in love with your smile.

译文：纵然伤心，也不要愁眉不展，因为你不知是谁会爱上你的笑容。

Don‘t waste your time on a man/woman, who isn‘t willing to waste their time on you.

译文：不要为那些不愿在你身上花费时间的人而浪费你的时间。

You don’t need someone to love in secret. We just stand by the river and feel sad when seeing the shadow in the water and thought that we r falling love with someone.

译文：暗恋是不需要对象的，我们不过站在河边，看着自己的倒影自怜，却以为自己正在爱着别人。

Tears dry on their own, but a broken heart needs time to mend.

译文：眼泪会自行风干，但破碎的心需要时间疗愈。

Loneliness speaks in quiet tongues, and love asks for a louder reply.

译文：孤独用无声的语言述说，而爱情却渴望热烈的回应。

The ache in your heart will heal, but the smile on your face may never return.

译文：你内心的痛会消散，但笑容可能再也无法如初。

Empty seats, once filled with laughter, now only echo loneliness.

译文：空座位，曾经充满欢笑，如今只剩寂寞回声。

The worst way to miss someone is to be sitting right beside them.

译文：最痛苦的方式是坐在某人身边，却只能想念。

I am so thin, what to warm others.

译文：我自己都如此凉薄，拿什么去温暖别人。

When you want to cry, don’t hold back, uncomfortable is yourself!

译文：想哭的时候，别憋着，难受的是自己!

这些句子都带有深刻的情感和哀伤，适合在需要表达或感受悲伤情绪时使用。希望这些句子能触动你的心弦。