Harry spends the week before Christmas enjoying himself. Fred and George sell a bunch of Canary Creams, which makes everyone suspicious of accepting food from others. Ron questions Hermione every chance he gets about whom she's going to the ball with, but she refuses to say. One evening in the entrance hall, Malfoy interrupts Ron to express surprise that anyone asked Hermione to the ball. Hermione waves and greets Moody as though Moody is behind Malfoy. Malfoy jumps and the trio laughs; Moody is nowhere to be seen.
Pay attention to the fact that all of Malfoy's bullying seeks to make his targets feel less than and as though they're not worthy of love or attention. By doing this, Malfoy is choosing the kind of person he wants to be, just the same as Harry and his friends are. This allows the reader a way to sympathize with Malfoy, as it shows he's a maturing teen just like everyone else in the novel.
Ron notes that Hermione's teeth look different, and Hermione mischievously says that when she went to Madam Pomfrey to fix Malfoy's curse, she let her shrink her teeth to less than their original size. As they reach the top of the staircase, Hermione points to Pigwidgeon twittering at students. Ron hands the letter to Harry and Harry reads it when they get back to the common room. Sirius reminds Harry that he can't get complacent and needs to stay out of trouble.
When Ron notices Hermione's teeth, it shows that he's beginning to learn from the debacle a few days ago and now recognizes that Hermione is an increasingly attractive young woman, at least in his opinion. Commenting on it allows Hermione to feel good about her appearance.
On Christmas Day, Harry wakes to Dobby's face close to his and yells. Dobby apologizes and offers Harry a present as Ron, Seamus, Dean, and Neville decide to open their own presents. Harry gives Dobby a pair of Uncle Vernon's old socks, which delights the elf. Ron throws Dobby another pair of socks and Mrs. Weasley's sweater. Dobby's gift to Harry is two hand-knitted socks, one with broomsticks and one with Snitches knitted into them. Harry spends the day eating, playing, and having a snowball fight.
The delight that Dobby takes in receiving these old socks shows Harry that acts of kindness don't need to be grand or elaborate to be effective; sometimes, making someone happy is as easy as giving them a pair of socks. By choosing to make Dobby happy in this way, Harry is then able to keep his friendship with the elf alive.
At seven, the boys head upstairs to get ready. Ron cuts the lace off of his dress robes before he and Harry meet Parvati in the common room. She's lovely in pink robes and leads the boys downstairs without Hermione. They meet Padma, who seems unimpressed with Ron. Ron remains fixated on finding Hermione as they watch other students arrive in the front hall. Harry sees Karkaroff lead his students in and sees Krum with a pretty girl he doesn't recognize. However, when McGonagall calls the champions and their partners to the side, Harry realizes Krum's date is Hermione. Several people seem amazed that Hermione looks so pretty, but Ron ignores her as he walks into the Great Hall.
When everyone is so shocked to see that Hermione is capable of making herself look conventionally beautiful, it shows that all of them--Harry and Ron included--have learned to think of Hermione as being only important or notable for her smarts. Her appearance makes it clear that Hermione is capable of being more than just the resident smart kid, while the fact that she's attending the ball with Krum shows that she's taking Dumbledore's request to be friendly with their guests to heart.
Harry and Parvati follow the other champions to the head table where the judges are seated. Percy is sitting where Harry assumes Mr. Crouch was supposed to sit. Harry sits next to Percy who immediately shares that he's been promoted and that Mr. Crouch isn't well. Harry notices that Hermione is deep in conversation with Krum about Durmstrang and listens to Dumbledore and Karkaroff argue about keeping their schools' secrets. He notices Hagrid a few tables away and smiles at Hermione, who's trying to teach Krum to say her name properly.
When Karkaroff gets upset about Krum spilling school secrets, it shows that unlike Dumbledore, Karkaroff doesn't necessarily see the value in forming friendships with foreign friends. Harry's apparent acceptance of Hermione and Krum attending together shows that, like Hermione, he also sees the value of having friends from other places.
When everyone is finished eating, Dumbledore waves his wand to clear dance floor. The band The Weird Sisters takes the stage and Parvati steers Harry onto the floor. Dancing is less embarrassing once others start dancing too but as soon as the song ends, Harry leads Parvati to where Ron and Padma are sitting. Ron glares silently at Hermione and Krum. Parvati accepts an invitation to dance with a Beauxbatons boy and Hermione soon takes her seat, happily sharing that Viktor is getting drinks.
Both Harry and Ron are being rude to their dates, which shows that neither of them thinks of Parvati and Padma as being especially worthy of their time and attention. This again shows how far Harry and Ron have to go as they mature emotionally and develop a sense of empathy for others.
Ron accuses Hermione of "fraternizing with the enemy," which baffles Hermione. Ron suggests that Krum only asked Hermione so that he could get information about Harry, jinx him, or get help with his egg. Hermione angrily reminds Ron that the Tournament is about making friends, and Harry says that he doesn't have an issue with Hermione going to the ball with Krum. Ron ignores this and Hermione walks away. Padma excuses herself to join Parvati just as Krum approaches with butterbeers, looking for Hermione. Ron sends him away as Percy arrives, thrilled that Ron is making friends with Krum--he says the point of the Tournament is to make friends.
Ron's accusations against Krum show that as far as Ron is concerned, the purpose of the Tournament is winning at all costs and creating real divides between Hogwarts students and students from other schools. This illustrates how even good characters like Ron can make choices that make them seem less good, while also pointing out that Voldemort isn't the only one suspicious of or hateful towards outsiders--anyone is capable of thinking like that.
Percy sits down next to Ron and he and Harry watch Fred and George accost Bagman. Bagman escapes them, comes over to say hi to Harry, and explains that the twins want help with marketing their joke products. Percy and Bagman begin to talk about Mr. Crouch and the Tournament as a whole and after a minute, Ron pokes Harry. They step outside where, curiously, they hear Snape and Karkaroff using each other's first names and talking about something that's getting clearer. A little further up the path, Harry hears Hagrid.
Bagman's comment about Fred and George asking for help with their joke wares reminds the reader that for Fred and George, adulthood is very close and soon, they're going to need to make it in the real world. Though this isn't actually why they're seeking out Bagman, Bagman knows that this is a logical and acceptable cover given the twins' age.
Noticing that Fleur and her date are kissing in a nearby rosebush, Ron refuses to let Harry lead him past them and instead pulls Harry into a bush behind Hagrid. Hagrid is talking to Madame Maxime, saying that he knows that she's "like him." He talks about his dad and his mum, who he says wasn't maternal. Harry notices a beetle and tries to concentrate on it as Hagrid asks Maxime which side she has "it" on, and says that he knows she's a half-giant too. Maxime shrieks, offended, and storms away. Ron looks serious, which tells Harry that there's more to being a half-giant than he knows.
Given the way that the novel has already offered insight into the ways that non-human creatures are treated by wizards, it's likely that giants are also unwelcome and treated with caution. Harry's desire to leave Hagrid alone for this private conversation shows that Harry is developing a sense of empathy and respect for his friends and understands the importance of giving his loved ones privacy for their secrets.
Back inside, Ron explains that giants are vicious, though Hagrid isn't, and it makes sense that he'd want to keep it secret. They discuss giants for the rest of the ball and are thrilled when it's over. On their way up the stairs, Cedric calls for Harry and quietly tells him to take a bath with his egg. He gives Harry the password for the prefects' bathroom and runs off to say goodnight to Cho. When Harry gets to the common room, Ron and Hermione are having a screaming match. Hermione yells that next time, he shouldn't ask her as a last resort and runs to bed. Harry stays silent, but he thinks Hermione is right.
When Cedric chooses to give Harry a hint in return, it shows that, like Harry, he believes in fairness and wants all the champions to be able to compete on equal footing. The fact that the reader only sees this happening among the Hogwarts students suggests that it's possible that it's only the Hogwarts students that feel this way, again showing that Dumbledore's school is, by design, kinder and more accepting.