YOU SAID:

when the tiger runs, it goes very fast, very fast indeed

INTO JAPANESE

虎が走るとき、それは非常に速く、実に非常に速く進みます

BACK INTO ENGLISH

When a tiger runs it goes very fast, really very fast

INTO JAPANESE

虎が走るときはとても速く、本当にとても速く走る

BACK INTO ENGLISH

When tigers run they run very fast, really very fast

INTO JAPANESE

虎が走るとき、彼らは非常に速く走る、本当に非常に速く走る

BACK INTO ENGLISH

When tigers run they run very fast, really very fast