YOU SAID:
I have a pen I have pineapple
INTO JAPANESE
私はパイナップルがあるペンがあります。
BACK INTO ENGLISH
I have a pen is the pineapple.
INTO JAPANESE
ペンを持っている、パイナップルです。
BACK INTO ENGLISH
I have a pen, it is pineapple.
INTO JAPANESE
私はペンがあります、それはパイナップルです。
BACK INTO ENGLISH
I have a pen, it is pineapple.
That didn't even make that much sense in English.