Past.

(+) I was born in 1992.
(-) I wasn't born yesterday.
(?) Was I born in 1992? yes I was.

(+)He saw a movie yesterday.
(-)He didn't see a play yesterday.
(?)Did He see a movie yesterday? yes , he did.

(+)He arrived from the airport at 8:00.
(-) He didn't arrive from the airport at 6:00.
(?) Did He arrive at 8:00? yes, He did.

(+) Tania liked tomatoes before.
(-) Tania didn't like tomatoes before.
(?) Did tania like tomatoes before? yes, she did.

(+)They were in Hermosillo last week.
(-) They weren't in Hermosillo last week.
(?) Were they in canada last week? no they weren't.