: You might be referring to the idea that while a person's profile may look "mature" or "ready" on paper, the actual experience of "maturing"—especially when balancing work, family, and studies—is physically and mentally "hard".
: For mature students (those over 21), "completing the paper" (essays or degrees) is notoriously difficult due to "identity challenges" and the lack of sympathetic support from employers or government services. matures hard
: In a literal sense, "semi-mature" refers to a specific type of Chinese Calligraphy Paper designed for hard/brush pen writing, where the maturity of the paper affects ink absorption. : You might be referring to the idea