forced smile

基本解释

I was not strong enough to disagree with you and I nodded my head with a forced smile.
我不夠堅強所以我沒有反駁你，我衹是點點頭露出勉強的微笑。
Another nonverbal sign of lying is a forced smile, which generally involves only the muscles of the mouth and not the rest of the face.
另一個說謊的征兆是強擠出來的笑容，這種笑容衹是調動了嘴部的肌肉而不是整個臉部的肌肉。
In a job interview, you may have experienced an interviewer’s flat affect and forced smile rather than a warm welcome that would have put you at ease.
在麪試的時候，考官要求你微笑，而不是熱情歡迎你的到來，讓你放松。

But when you hold a pencil further back in your mouth, you are forced to smile.
FORBES: When You're Smiling