心情还不错用英文表达为： in a good mood.
mood：
n.情绪;心情;坏心境;坏脾气;气氛;氛围
复数： moods
He was not in a good mood that day.
他那天心情不好。
She's in a good mood today.
她今天心情很好。
Luckily I was feeling in a good mood.
幸好我当时情绪好。
He is clearly in a good mood today
明摆着，他今天心情不错。
Go and tell him while he is in a good mood.
趁他心顺的时候去跟他说。
People were in a pretty good mood
人们的心情十分舒畅。
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