How does a nymph differ from an adult insect (three things)?

Answer 1

lWings absent or non-functional (if the adult has
wings), reproductive organs immature and not
completely formed anatomically, no further size
increase, usually different coloration and sometimes shape from the adult, sometimes a
major change in ecology and habits from nymph to
adult, especially in those with aquatic nymphs.

Answer 2

Size, functional wings and reproductive ability

Answer 3

Size, color and ability to reproduce. That's my guess by the way not fact.

Answer 4

Size, color and tenderness of chitin.