YOU SAID:

pillows are pillows because they are made out of pills named pillows

INTO JAPANESE

枕は枕と呼ばれる丸薬から作られているので枕です

BACK INTO ENGLISH

Pillow is a pillow because it is made from pill called pillow

INTO JAPANESE

枕は枕と呼ばれる枕から作られているため、枕です。

BACK INTO ENGLISH

Pillow is made of pillow called pillow, so it is a pillow.

INTO JAPANESE

枕は枕と呼ばれる枕で作られているので、枕です。

BACK INTO ENGLISH

Pillow is made of pillow called pillow, so it is a pillow.