YOU SAID:

the fat cat sat on the mat and went rat-a-tat-tat

INTO JAPANESE

太った猫はマットの上に座って、ガタガタと鳴いていました

BACK INTO ENGLISH

The fat cat was sitting on the mat and was rattling

INTO JAPANESE

太った猫がマットの上に座ってカタカタしていました

BACK INTO ENGLISH

A fat cat was sitting on the mat and rattling

INTO JAPANESE

太った猫がマットの上に座ってカタカタしていました

BACK INTO ENGLISH

A fat cat was sitting on the mat and rattling