Suyoung Mel Kwon
Selected Works
EducationLearning LanguageNLPAI

“Memorizing foreign words shouldn't feel like torture.”

PhoniTale: AI Memory Tricks for Foreign Words

AI Research Project

Period
March 2025- June 2025
Role
Evaluation DesignUX/UI DesignPlatform DevData Analysis
Team
Evaluation Lead (me)*2 engineers*1 PhD student3 faculty advisors
Org
CMUSchool of Computer Science, Language Technology Institute

* Co-first author

10s Summary

What?

Built an AI that helps you memorize foreign words by linking them to sound-alike words in your own language. Published at EMNLP 2025.

Why?

For languages that sound very different, like English and Korean, LLM-based methods couldn’t produce good mnemonics.

How?

Mapped foreign sounds into native syllables, matched them to real words, and wove them into a memorable sentence. It worked as well as mnemonics written by human experts.

Overview

What is PhoniTale, and what did I do here?

OVERVIEW

PhoniTale

: from Phonology + Mnemonic + Tale

An AI system that creates fun, memorable mnemonics for learning foreign vocabulary. It’s as creative as human-made ones, and the first built to work across languages with completely different sound systems.

MY ROLE

Human Evaluation Lead

As a Visiting Scholar at CMU’s School of Computer Science in Spring 2025, I worked with a team on this NLP + HCI research project. I led the human evaluation: designing the study, building the web platform to run it, and analyzing the results.

I also researched the linguistic background, reviewed related literature, and contributed to system architecture design and paper writing alongside my engineering teammates.

RESULT

Built PhoniTale,
Published at EMNLP 2025
Main Conference

Read Paper ↗
Presenting the PhoniTale poster at EMNLP 2025

Built Novel System

First system to generate mnemonics for typologically distant language pairs, like English and Korean.

Outperforms LLM-only

PhoniTale’s specialized phonological modules outperform pure LLM generation.

Matches Expert Recall

PhoniTale’s mnemonics scored 0.609 vs. 0.590 for expert-made ones in recall tests.

Infinitely Scalable

Generates high-quality mnemonics for any word, with zero manual effort.

Process

Why did this project start, and how did we approach it?

BACKGROUND

It All Started with Our Own Frustration

We were studying for the GRE (grad school applications in the U.S.), and English vocabulary just wouldn’t stick.

Studying vocabulary flashcards for the GRE
PROBLEM

So Why Did the LLM Get It So Wrong?

English and Korean don’t sound alike. Not even close. Here’s what LLMs miss:

1. Different Structure

English letters line up in a row. Korean letters stack into blocks.

2. Different Syllable Length

One English syllable often stretches into several in Korean.

3. Missing Sounds

Sounds like "th" don’t exist in Korean.

4. Different Rules

English treats /k/ as one flexible sound. Korean splits it into three distinct letters.

Goal

We Shaped Three Goals

Human-level Effectiveness

Generate mnemonics as memorable as ones made by human experts.

Fully Scalable

Automate the entire process
with no manual work required.

Works for Any Language Pair

Build a system that works for any two languages with different sound systems

APPROACH

We Designed PhoniTale to Really "Listen"

See how “Squander” becomes a Korean keyword, and then a memorable cue.
* L1 = native language, L2 = language you’re learning

PhoniTale: from Phonology + Mnemonic + Tale

Transliteration

Converts the 🇺🇸 L2 word’s sound into the closest 🇰🇷 L1 sounds

/sɯkʰwantʌ/

→

Segmentation

Divides the new sound sequence into valid 🇰🇷 L1 syllables

/sɯ/ - /kʰwan/ - /tʌ/

→

Keyword Match

Finds 🇰🇷 L1 dictionary words that match the sound segments

🇰🇷 세관 - 더
(/sɛɡwan/ - /tʌ/)

→

Cue Generation

An LLM weaves the 🇰🇷 L1 keywords into a memorable sentence.

🇰🇷 세관에서 시간을 더 낭비했다.
(/sɛ.ɡwan ɛ.sʌ si.ɡɑn.ɯl. tʌ. nɑŋ.bi.ɛt.t*ɑ/)

Evaluation

What did I design to prove our idea and how did it turn out?

OBJECTIVE

Here's What We Set Out to Prove

  1. PhoniTale matches human-expert mnemonics.
  2. It outperforms older AI-based methods.
EVALUATION DESIGN

So Here's How I Designed the Test

To prove it, I designed a study measuring PhoniTale’s effectiveness with real human learners, both quantitatively and qualitatively.

KSS (Human Expert) vs OGR (Older SOTA) vs PHT (Our Model), N = 17 each

Groups & Participants

We compared human, AI baseline, and our model side by side, using Korean-native adults. Participants were screened through an English proficiency test, then randomly assigned across the three groups.

Instruction → Learning → Testing (Recognition → Generation) → Survey, 3 sets

Procedure

Following methods from prior work, participants learned words with mnemonics, then were tested on recognition and generation, and rated each mnemonic’s helpfulness and appeal.

PhoniTale evaluation web platform screenshot

Web Platform

I built a custom web platform to reach remote participants, capture precise timing data, and eliminate variables unrelated to the mnemonics themselves.

PLATFORM DESIGN

How I Approached the Platform Design

A simple, focused interface built specifically for running this evaluation.

1. Key Path

Mapped the essential flow participants needed to follow, based on the evaluation procedure.

Key path flow diagram

2. Wireframe

Studied existing language-learning apps to explore layout patterns and core UX decisions.

Wireframe exploration

3. Design

Prioritized a simple, distraction-free interface, so participants could focus on the task, not the design.

Key Component

Key component mockup

Matching English and Korean keywords were color-coded to show their phonetic link, while distinct font styles separated the word’s meaning from the mnemonic story, making the logic behind each cue visually clear at a glance.

Learning

Learning screen mockup

Test - Recognition

Recognition test mockup

Test - Generation

Generation test mockup

Survey

Survey screen mockup
PLATFORM DEVELOPMENT

From Design to Fully Working Product

In spring 2025, vibe coding was just taking off, and I wanted to try it firsthand.
So I designed the system architecture and built the entire platform myself, solo.

System Architecture

System architecture: group-specific URL to web frontend to backend (AWS), with group-specific test set and DynamoDB database

Tools

Cursor and Claude
FINDINGS

The Data Proved PhoniTale Works!

I analyzed data from 51 participants, collected through the platform, to test both goals, and the results confirmed them.

Chart comparing recognition and generation recall across the three groups

1. PhoniTale matches human-expert mnemonics

In the generation task, PhoniTale scored 0.609, with no statistically significant difference from human-expert mnemonics (0.590).

2. PhoniTale outperforms older AI-based methods

PhoniTale significantly outperformed the older AI method (OGR) in generation accuracy, 0.609 vs. 0.539 (p < .05).

+ One More Thing: Preference ≠ Performance

Interestingly, people still preferred human-made cues, even when PhoniTale helped them remember just as well.

Reflection

What did I experience and learn?

New Experience

1. First Step into AI Research: My first project in AI/NLP research, from idea to publication.

2. Built a System Solo: Went beyond planning to design and build the entire evaluation platform myself.

3. Published at a Top-Tier Conference: Presented our work at EMNLP 2025 Main Conference.

New Learnings

1. What Research Really Means: I learned what research actually looks like, turning a personal pain point into a real question, building an approach to answer it, and proving it works. That full arc taught me more than any single step could.

2. The Barrier to Building Has Dropped: Beyond planning, I directly handled development and data analysis for the first time. I realized that with curiosity and an idea, anyone can now build something and put it into the world. This makes me want to focus less on the tools themselves, and more on intent and value.

3. New Challenges Compound: Diving headfirst into unfamiliar territory pushed me a level up, in both skill and perspective. I want to keep embracing the unfamiliar and growing from it.

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