Fast
い adjective
Just like the meaning of the kanji (fast) this adjective also means fast.
はやい
Remember how 早い means "early"? If you are early to something, it probably means you moved fast to get there. These two words share a reading (and have similar meanings, in a way, as well!).
うちの兄はクロールで泳ぐのが速い。
My older brother is a fast crawl swimmer.
この車のスピード、さすがに速すぎない？
Isn't this car going too fast?
大谷君は、足も速いし、顔もイケメンだし、投手としても、バッターとしてもパーフェクトなんだよ。
Ohtani is a fast runner, handsome, and he's perfect as a pitcher or a batter.