
Leonard, what if you have
an allergic REACTION...
The Big Bang Theory Season 8, Episode 9

If the two of you engage in intercourse,
this will create the biochemical REACTION...
The Big Bang Theory Season 2, Episode 9

Yeah, my initial REACTION is no.
The Big Bang Theory Season 2, Episode 22

Look at her REACTION
to the good-night kiss.
The Big Bang Theory Season 2, Episode 1

My friend
is having allergic REACTION to peanuts.
The Big Bang Theory Season 1, Episode 16