Spider-Man: Far From Home is full of crackling dialogue from its entire cast. The movie makes great use of its young stars in a classic teenage comedy that just happens to also be a superhero movie. Some of the best quotes from the movie tend to come from one character in particular: MJ.
Peter Parker's friend and partner in defending London against evil is a constant source of quirky, dry wit. Fans never know if what MJ is saying is completely serious, which is part of the charm of a lot of the funny (and observant) things she says.
"It’s not like anybody really pays attention to you."
One of the best exchanges MJ shares with Peter comes at the end of the movie. Once they've returned home from Europe, they go their separate ways at the airport. It's clear they don't want to part quite yet, despite the expectation they're going to see a lot of each other in the near future. Peter is worried others have figured out his identity - and they have - but MJ tells him not to worry because "It’s not like anybody really pays attention to you."
"I’m sorry! Okay? I just, I’m obsessed with telling the truth even if it hurts other people’s feelings."
During the climax of the movie, a few of the students get caught up in the attack on London by Mysterio (likely a candidate for an eventual MCU Sinister Six). The students, including MJ, Ned, Betty, and Flash, all freak out a little bit. Ned fears he's wasted his life on video games. When MJ keeps it real by acknowledging the fact that they are all probably going to die, she responds to the others' anxious pleas for her to stop by keeping it one hundred.
"If you saved us, why are we about to die?"
During the attack on London by the super-Elemental (really just an illusion of Mysterio), Flash Thompson (played by Tony Revoloi, who also auditioned for other MCU roles) realizes that his live streaming of the event likely played a role in Spider-Man's intervention. He thinks he's saved them but MJ brings him back to Earth. "If you saved us, why are we about to die?" she asks as the monster Elemental Mysterio has unleashed closes in on Tower Bridge.
"Yeah, you should definitely believe everything you read on the Internet."
In the aftermath of the first Elemental attack in Venice, the group of students from MidTown High debate what exactly happened. Most of them search online for information on the water-based Elemental (who is a subtle nod to classic Spider-Man villain Hydro-Man).
Flash Thompson claims he read the Elemental is Morris Bench, a surfer exposed to an underwater generator. MJ calls him out on this in her classic hurts but its true fashion.
"You know Suzanne Yang thinks that you’re a male escort?"
After the attack on Prague (during which Peter launches the infamous career of the Night Monkey) he and MJ have a conversation that doesn't go the way he thought it would. MJ just puts it out there: she knows he's Spider-Man. When Peter denies it, the conversation turns sideways. MJ tells Peter that one of their classmates, Suzanne Yang, thinks Peter is a male escort. He vehemently denies this, and MJ backs him into a rhetorical corner he eventually concedes to.
"Because I was only like sixty-seven percent sure."
Peter eventually admits to being Spider-Man once they get back to the hotel the students are staying at. This takes MJ by surprise because as she says, she was only 67% sure. The scene in which Ned walks in on their conversation as Peter gets into gear is a classic moment of shock for everyone involved. MJ had her suspicions, but like a lot of other things she says, she may not be completely serious. This time, her instincts turned out to be 100% accurate.
"I read it was secretly built as a mind control antenna to create an army of the insane."
The students are due to go to Paris after Venice, which Peter is very much looking forward to. He plans on giving MJ a special gift there and asking her out on a date. The group never gets there, diverted to Prague thanks to the efforts of Nick Fury (who wasn't really Nick Fury). Peter and MJ nevertheless have a cute conversation about going to the Effiel Tower, though. Peter talks about its romantic allure; she talks about its place in some pretty wild conspiracy theories.
"And therefore I have value?"
One of the sweetest moments in the film comes as the group prepares to go to the opera in Prague. Peter is squeezed between his want to hang out with MJ and his classmates and the impending sense of dread relating to the Elementals that have already attacked them in Venice.
In an exchange that exemplifies who they are, Peter compliments MJ by saying she looks pretty. She throws him a curveball by replying "And therefore I have value?" Turns out she's playing with him. Maybe.
"What is it with you and Spider-Man?"
The attack in Venice is a shock to everyone. It's also revelatory for a lot of the characters. Peter and MJ discover more about themselves and their feelings for each other. And Flash gets kind of honest, too. He admits to his adulation of Spider-Man, prompting MJ to ask what that is about exactly. Flash says "He protects the neighborhood and, you know, he's inspiring. He inspires me to be a better man." Right after, Peter Parker walks in and Flash insults him.
"What's up, dorks?"
MJ's best one-liner in the entire movie is really her first. She walks up to Peter and Ned in class while Peter is discussing how to ask MJ out on a date. Things get super awkward super fast. This is par for the course with these two, but since The Snap, it's clear their interaction has taken on a new tenor. Peter is motivated to be more proactive in his life, while MJ is ostensibly still herself, although it's clear from the conversation that follows that Peter doesn't have a good handle on that.