Simplify the following text for a Grade 9 native English-speaking person.
Original: In biology , the imago is the last stage of development of an insect , after the last ecdysis of an incomplete metamorphosis , or after emergence from the pupa where the metamorphosis is complete .
Simplified: In biology , the imago is the last stage in the development of an insect . It comes after the last ecdysis of an incomplete metamorphosis , or after emergence from the pupa where the metamorphosis is complete .