YOU SAID:

if pigs can fly why can't we humans fly?

INTO JAPANESE

豚が飛べるならなぜ人間は飛べないのか？

BACK INTO ENGLISH

If pigs can fly, why can't humans fly?

INTO JAPANESE

ブタが飛べるのならなぜ人間は飛べないのでしょうか？

BACK INTO ENGLISH

If pigs can fly, why can't humans fly?