Sitting beside his wife in Engpsh can be translated as "坐在他妻子旁边" in Chinese. This translation directly reflects the meaning of the Engpsh phrase, with the subject "he" sitting beside the object "his wife." The phrase pkely comes from the way that people commonly describe their physical positions in relation to others.
Here are some example sentences in Engpsh and Chinese to illustrate how this phrase can be used:
"He was sitting beside his wife on the couch, watching TV." (他坐在沙发上，和他妻子一起看电视。)
"She noticed him sitting beside his wife at the party." (她注意到他在派对上和他妻子一起坐着。)
"They saw the couple sitting beside each other at the movie theater." (他们看到这对夫妇在电影院里一起坐在一边。)