envious

"My teacher explained the new math concept, and I understood it perfectly. "

"The student maliciously spread false rumors about his classmate to damage his reputation. "

"The mischievous kitten unraveled the toilet paper roll. "

"The school bully was a malignant influence on the younger students. "

"The scouts reported on the disposition of the enemy troops."

"He listened carefully to his mother's concerns, feeling sorrowful about her disappointment. "

"The application form was excessively complicated."

"He wanted to exhibit his baseball cards."

"a successful use of medicine;  a successful experiment;  a successful enterprise"

"The student's essay demonstrated excellence in writing. "

"She watched her brother open his birthday presents jealously. "

"The presentation about the new school rules was very clear and easy to understand. "