If you are complimentary about something, you express admiration for it.
flattering
The staff have been very complimentary, and so have the customers.
职员们对此非常赞赏,顾客们也是。
A complimentary seat, ticket, or book is given to you free.
He had complimentary tickets to take his wife to see the movie.
他有赠票,可以带他妻子去看那部电影。