YOU SAID:
today, we went to the library and got coffees
INTO JAPANESE
今日は図書館に行ってコーヒーを飲んだ
BACK INTO ENGLISH
Today I went to the library and drank coffee
INTO JAPANESE
今日は図書館に行ってコーヒーを飲みました
BACK INTO ENGLISH
Today I went to the library and drank coffee
That didn't even make that much sense in English.