The phrase "tough times" can be replaced with several synonyms such as difficult times, hard times, challenging times, trying times, and rough times. All of these synonyms indicate a period of struggle or adversity. "Difficult times" emphasize the challenging nature of the situation, while "hard times" imply a period of hardships that require strength to overcome. "Challenging times" suggest difficulty but also the possibility of growth and improvement. "Trying times" convey the emotional strain and stress that comes with tough situations. Lastly, "rough times" imply an unpleasant, turbulent period that requires resilience and perseverance. Regardless of which synonym is used, they all convey the same message of perseverance during trying periods.