Translation of "Slowest" in Russian

They have the slowest digestion rate of any mammal.

Среди всех млекопитающих у ленивцев самое медленное пищеварение.

- The slowest one to make a promise is the most faithful one in keeping it.
- He who is slow to promise is best in keeping them.

Кто самый медленный на обещания, тот самый скорый на выполнение.