задание 1
adjective: brainy, brainless, brain dead
nouns: brainbox, brainwave
verbs: use your brain, be the brains behind
idioms: brainwash, pick someone's brains, brainstorm
задание 2
1) brainstorm
2) brainy
3) brain dead
4) is the brains behind
5) brainwave
6) brainwashed
7) pick your brain
8) brainless
9) brainbox
10) use your brain