They are felicxa and malfelicxa.
The Esperanto word for happy is "feliĉa" and the word for sad is "malĝoja".
The Esperanto words for salt and pepper are salo are pipro.
The Esperanto words for safe and dangerous are sekura and dangera.
The Esperanto words for generous and stingy are sindona and malgrandanima.
The Esperanto words for loud and soft are lauta and malvarmeta.
The Esperanto words for pants and skirt are pantalonoj and jupo.
The opposite of the word 'sad' is happy!
Words meaning happy are gay, joyful, glad, rejoicing, gleeful, overjoyed, elated Words meaning sad are depressed, morose, unhappy, downcast
The Esperanto words for far and away are malproskime and for.
The Esperanto words for astronaut and cosmonaut are very similar to the English words. In Esperanto you would use astronaŭto and kosmonaŭto.
The Esperanto words for boring and fun are enuiga and amuza.
The Esperanto words for near and far are proksime and malproksime.
The Esperanto words for car and driver are aŭto and ŝoforo.
The Esperanto words for alive and dead are vivas and mortinto.
The Esperanto words for hungry and full are malsata and plena.
The Esperanto words for broken and fixed are rompita and fiksa.
The Esperanto words for foreign and native are eksterlanda and denaska.
The Esperanto words for hard and soft are malfacila and malvarmeta.