YOU SAID:
Guess who got his free taco
INTO JAPANESE
誰が彼の無料タコスを手に入れたと思います
BACK INTO ENGLISH
I think who got his free tacos
INTO JAPANESE
私は誰が彼の無料タコスを手に入れたと思う
BACK INTO ENGLISH
I think who got his free tacos
That didn't even make that much sense in English.