YOU SAID:

I have a duck in my pocket

INTO JAPANESE

ポケットにアヒルがいます

BACK INTO ENGLISH

There is a duck in the pocket

INTO JAPANESE

ポケットにアヒルがいる

BACK INTO ENGLISH

The presence of a duck in the pocket

INTO JAPANESE

ポケットの中のアヒルの存在

BACK INTO ENGLISH

the presence of ducks in pockets,

INTO JAPANESE

ポケットの中のアヒルの存在、

BACK INTO ENGLISH

the presence of ducks in pockets,