Idiom: must-see; used as an adjective.

First Example:
Samantha: I’m trying to decide what movie to
watch tonight.  Can you suggest any old
movies?  I want something romantic.
Rebecca: Have you seen Casablanca? 
Samantha: Yeah, I cried at the end.
Rebecca: What about Gone With the Wind? 
Samantha: Yep – but that’s old.  Maybe something a little newer.
Rebecca: I assume you’ve already seen Titanic? 
Samantha: Actually, I haven’t.
Rebecca: Really? You have to watch Titanic! It’s one of the must-see movies of the 90s!  I thought everyone had already seen it.  How could you have missed it? 
Samantha: Uh, I was born in the 90s.

Meaning: “Must-see”
is an adjective that means something should be seen by everyone. This idiom is
usually used for movies and plays.  In
the example, Rebecca says that Titanic
is a must-see movie, which means she
thinks everyone should see Titanic.  

Here is another example:
Stephanie: I saw the musical The Book of Mormon last night on
Broadway.
Harry: How was it? 
Stephanie: It was just OK.  I had heard so many good things, I thought I was going to love it, but I
wouldn’t say it’s a must-see.
Harry: That’s too bad.  I was excited to see it.

Meaning: In this case, Stephanie said that The Book of Mormon wasn’t a must-see, so she doesn’t think everyone
should see it.  notice that even when
used as a noun, there is a hyphen between the two words.
This idiom is from the upcoming
edition of LSI’s book “Reading Horizons,” which will be used in the
Level 6 Reading classes. For more information, please visit https://www.languagesystems.com/