Love at First Sight
Love at First Sight is one of the most classic tropes. You lock eyes with someone, and your heart (and ideally their heart) is immediately swept away in a torrent of passion. Something gets in your way for a while-- but don't worry. You find your way back.
Examples: Romeo and Juliet, Blue is the Warmest Color, Anna Karenina
Often a logistical nightmare, Secret Baby happens when someone has a really good reason to not disclose the existence of a child to their ex-partner. Later, the ex finds out and they fall back in love.
Examples: Mamma Mia!, the love story part of What a Girl Wants
Updated Fairy Tale
The Disney Channel lives for this trope (see examples below). Straightforwardly named, Updated Fairy Tale is a modern twist on old romantic favorites.
Examples: A Cinderella Story, Another Cinderella Story, A Cinderella Story: Once Upon a Song, Ever After
Enemies to Lovers
As they say, aren’t love and hate just a hairsbreadth apart? Enemies to Lovers happens when one or both parties despise each other, but then the heat of their hatred turns into the flame of desire.
Examples: Anne of Green Gables, arguably Pride and Prejudice, Princess Diaries 2: Royal Engagement
Marriage of Convenience
Instead of marrying for love, Marriage of Convenience happens when a series of extenuating circumstance – financial, diplomatic, or otherwise – causes to characters to go to the altar. But don't worry; because after they get married, they fall in love.
Examples: The Hunger Games (sort of), Mr. and Mrs. Smith, Brighter than the Sun
With some creative acrobatics from the author, some whacky situation causes two people to pretend they are a couple. Of course, they end up falling in real love.
Examples: that one scene in Leap Year, The Duke and I, The Proposal, 10 Things I Hate About You
Unalterable circumstances tear two lovers apart and they find their way back together later in life.
Examples: The Odyssey, Letters to Juliet, also Mamma Mia!, The Notebook
Professional ethics who? Student/Teacher relationships are when the crush on your sexy and smart teacher-governess-tutor-professor somehow comes to fruition.
Examples: Pretty Little Liars, Legally Blonde
In Love with Best Friend’s Sibling
This trope offers an opportunity for a lot of angst, as each of the three people involved in the dynamic is forced to navigate between two of their closest loved ones.
Examples: Princess Diaries, Harry Potter
Friends to Lovers
Perhaps one of the most realistic of the tropes, Friends to Lovers involves growing sexual tension, long awaited first kisses, and strong emotional connections. Often the timing is off, or there are reasons to stay apart. But, of course, they end up together and in love.
Examples: 13 Going On 30, The Office, When Harry Met Sally
Deception, miscommunication, and often gender-bending, collide to make the Mistaken Identities trope. There is a high likelihood of moral ambiguity and/or creepiness here, so tread carefully.
Examples: She’s the Man, Mulan, Twelfth Night