YOU SAID:
She went to the park, yesterday.
INTO JAPANESE
彼女は昨日公園に行った。
BACK INTO ENGLISH
She went to the park yesterday.
INTO JAPANESE
私は昨日公園にいきました。
BACK INTO ENGLISH
I went to the park yesterday.
INTO JAPANESE
私は昨日公園にいきました。
BACK INTO ENGLISH
I went to the park yesterday.
That didn't even make that much sense in English.