Wishing (التمني) expresses desire for something not presently attained; it may be impossible or possible but not confidently expected. Its primary particle is layta (ليت).
«لَيْتَ الشَّبَابَ يَعُودُ»
Would that youth could return.
The past cannot literally be restored, yet the particle conveys the intensity of longing. By contrast, when an anticipated good is reasonably hoped for, the meaning may be closer to expectant hope (الترجي). Not every statement about a desirable future is a wish: the utterance must present a desire for its attainment.