YOU SAID:

if she weighs the same as a duck, she's a witch

INTO JAPANESE

彼女はアヒルと同じ重量を量る場合、彼女は魔女です

BACK INTO ENGLISH

If she weighs the same as a duck, she is a witch

INTO JAPANESE

彼女はアヒルと同じ重量を量る場合、彼女は魔女です

BACK INTO ENGLISH

If she weighs the same as a duck, she is a witch