YOU SAID:
He dropped in on us from time to time.
INTO JAPANESE
彼は時々私たちのところに立ち寄った。
BACK INTO ENGLISH
He stopped by us from time to time.
INTO JAPANESE
彼は時々私たちに立ち寄った.
BACK INTO ENGLISH
He stopped by us from time to time.
That didn't even make that much sense in English.