Answer: for the first exercice you have to underline the adjectives and put a cross under the word that the adjectives are describing like for the first sentence you underline the word "baleine" and u put a cross under the words "L'énorme" and "bleue" .
For the exercice number 2 im not sure so i will only tell you to underline
1)"en foret"
2)"de la classe"
3)"de CM2"
to surround:
1)"de"
2)"de"
3)"de"
and to put a cross under:
1)"les enfants"
2)"La maitresse"
3)"les eleves"
And finally for the 3rd exercice you have to put a adjective wich is a color like blue, red
1) jai eu une peur bleue
2) Avoir la main verte/rouge
3) Piquer une colère noire
4) Donner le feu vert
hope i helped :)