Note that many synonyms do not have exactly the same meaning; take the time to learn the differences.

Bad: awful; woeful; pitiful; pathetic; dire; atrocious; abysmal; shocking; soul-destroying

Beautiful: pretty; handsome; gorgeous; picturesque; hot; sexy; photogenic; sublime

Big: massive; ginormous; massive; humungous; enormous

Boring: dull; tedious; mind-numbing

Clever: intelligent; smart; brainy; genius; brilliant

Fashionable: stylish; cool; hip

Fast: quick; lightning

Fun: enjoyable; amusing; entertaining

Funny: amusing; hilarious

Good: great; excellent; fantastic; magnificent; marvelous; brilliant; stupendous; amazing; awesome; heavenly; out of this world

Interesting: fascinating; mesmerizing

Nasty: mean; vicious; spiteful

Nice: kind

Rude: mean; impolite

Serious: important; stoic; unamusing

Slow: snail-like

Small: tiny; minute; teeny; miniscule

Smelly: malodourous

Soft: cushioned; fluffy

Strong: mighty; muscular

Stupid: idiotic; moronic; retarded; dumb; slow

Tasty: delicious; heavenly

Tough: durable; sturdy

Ugly: hideous; revolting; disgusting; an eyesore

Weak: puny; feeble

Well: healthy; fit