I assume you are referring to Chapter 11 of "Frankenstein". The creature stays so long by the fire pit because he had never seen fire before, and it is a great relief to him to finally get warm. He examines the fire, finds out that it burns when touched, realizes that it is made of wood, and that the roots which he eats taste much better when roasted. He does his best to maintain the fire, but he has to leave it in search of food. Finally, when he leaves it, he "laments" because he doesn't know how to make fire again.
The answers would be good and benefit because antonym means opposite, so what's the opposite of harm, well its good of course.
A adjective phrase is a phrase the head of which is an adjective.
Rush
Difficulty
Steady
Holding
Engages
Blind
Provisional
Pursuit