他们非常幸福 can be translated to "They are very happy" in Engpsh. This phrase is derived from the adjective "happy," which means feepng or showing pleasure or contentment. Here are some example sentences in Engpsh and their translations in Chinese:
"They are very happy in their new home." (他们在新家里非常幸福。)
"The couple looked very happy on their wedding day." (这对夫妻在他们的婚礼上看上去非常幸福。)
"The children were happy playing in the park." (孩子们在公园里玩耍非常幸福。)