She said she was enjoying herself but her smile was forced.

她说自己很快活，但是她的笑容很勉强。

《牛津词典》

Wherever she went, she'd remember to bring me wonderful gifts, but her smile has been the greatest of all.

无论她去到哪里，她都会记得给我带一些很棒的礼物，但她的微笑才是最棒的。

youdao

She tried to smile, but instead tears came to her eyes.

她试图微笑，但泪水却涌了上来。

youdao

Her eyes showed traces of tears, but her lips were bravely curved in a smile.

VOA: special.2010.05.15

She kept her smile but never mentioned her opponent's name.

NPR: Sarkozy Wins Resounding Victory in French Vote

Her husband looked tired and tense, but he would glance at her and smile.

CNN: A Syrian woman's year of love and fear

At first, she had hardly any control over her face, but she can now muster a bit of a smile, and her doctors say with time she should be able raise her eyebrows and make other facial expressions.

CNN: Face transplant recipient's goal: A kiss