Cool MateFor Duolingo English Test candidates
60 minutes. $59.
Train the ear it adapts to.
Real 3-second clips from films, news, and talks. The chunks and phrases natives actually use. Spaced so they stick. Trains the speed, integrated micro-tasks, and adaptive pace the DET pushes you to from question one.
4.8 stars · CEFR A1 to C2 · 13 languages · Free forever
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A 3-second chunk. The kind your ear needs to meet daily.
No email gate. No paywall. Just the same kind of chunk that lives inside the app, with the DET-relevant context shown after you guess.
Chunk
“on the whole”
Get hundreds more in the app
Honest by design
What Cool Mate is, and what it is not.
What we focus on today
- Listening fluency from real native audio at full speed
- Chunks and phrases that lift adaptive trajectory and speaking samples
- Vocabulary that sticks through spaced repetition
- Pronunciation modeling from native voices
Not in scope today
- DET-specific question patterns (Read and Complete, Type What You Hear)
- AI proctoring practice or webcam-pace drills
- Full DET-format mock tests
On the roadmap
How to use Cool Mate with your prep
- Daily 5 to 15 minutes of Cool Mate, every day
- Official Duolingo English Test Practice Test for the real format
- Arnia DET or DET Prep Guide for question-pattern drills
- Cool Mate covers the daily practice the others cannot
The thesis
Words get you to 100. Chunks get you to 130.
Natives do not assemble sentences word by word. They snap pre-built chunks into place. The DET adaptive engine rewards this in your Speaking and Writing samples. Word lists hit a ceiling. Chunks break through it.
Real chunks Cool Mate teaches in real video context:
Speaking sample openers
- I'd say
- to be honest
- on the whole
- from my perspective
Writing sample chunks
- it can be argued that
- for example
- in conclusion
Interactive Listening hedges
- it depends on
- I'd have to say
- it's worth noting that
Type What You Hear cues
- moving on
- having said that
- in other words
Word-list approach
Memorize ubiquitous, mitigate, antithesis. Hope your brain reassembles them at DET speed on test day. People forget 50% in 24 hours and 80% in a week.
Chunk approach
Learn 'for example' as one move, inside a real clip from a real talk. Meet it again right before you'd forget. The speaker's voice anchors the memory.
Same time investment. Very different test result. This is why 5 minutes of Cool Mate beats an hour of word-list grinding.
Every DET micro-task, mapped
How chunks pay off across the DET.
Speaking samples
Stop freezing on the writing-sample and speaking-sample tasks. Chunks are pre-built, your mouth produces 'from my perspective' or 'on the whole' without translating from your L1. The AI hears fluency. You hear yourself sounding like you've spoken English for years.
Listening (Type What You Hear, Listen and Speak)
Natives speak at chunk speed: 3 to 4 words per second, often blurred. If you parse word by word, you fall behind. Cool Mate trains your ear to grab the chunk, not the words inside it. Real accents (UK, US, AU, IN, CA).
Writing sample
The DET AI rewards lexical resource. The highest-band responses deploy chunks like 'it can be argued that', 'for example', 'in conclusion'. Cool Mate's collections feed you these in the contexts where they actually appear.
Reading (Read Aloud, Read and Complete)
Two wins. First, raw vocabulary breadth for the Read and Complete task. Second, chunks unlock idiomatic meaning that word-by-word lookup destroys ('by and large', 'in light of'). You skim faster, infer better, finish on time.
DET-specific drills
Not in scope today. We don't drill Read and Complete or simulate AI proctoring. Pair Cool Mate with Official DET Practice or Arnia DET. Naming alternatives is trust, not weakness.
Find your starting score
DET scores map to CEFR. CEFR maps to Cool Mate.
Cool Mate tags every clip and collection with a CEFR level so you start at the right speed. Pick your target DET score, then practice at the matching CEFR level. Climb from there.
Score 85 to 95
Build the everyday vocabulary and listening pace to walk into the test without panicking.
B1Score 100 to 115
The score that opens most undergraduate programs. Subtitles come off here.
B2Score 120 to 135
The score for top universities and graduate programs. Idioms, register, and the right preposition every time.
C1Score 140 to 160
Native-like nuance. The score most candidates do not need, but the one where Cool Mate keeps paying off after the test.
C2How it works
Built to fight the forgetting curve.
People forget. Fast. 50% of new vocabulary is gone in 24 hours. 80% in a week. Memorization loses every time.
01
Real 3-second clip
From a real show, news segment, or talk. Your brain encodes the speaker, the scene, and the line. Episodic memory beats rote memory.
02
Answer the prompt
Tap once. We measure if you got it. No essays to write. No daily counter to protect.
03
Spaced repetition times the next review
Hard chunks come back tomorrow. Easy ones drift further out. We meet you again right before you'd forget.
Built on the Leitner spaced repetition system (1972) and 50 years of memory research.
How Cool Mate compares
Why daily Cool Mate beats one-shot DET prep guides.
Cool Mate is the daily companion. The others are the question-pattern drills. Use them together for the strongest DET prep.
| Feature | Cool Mate | Official DET Practice | Arnia DET | DET Prep Guide | |
|---|---|---|---|---|---|
| Real native video sources | ✓ | ✓ | ✓ | ✓ | ✓ |
| Spaced repetition built in | · | · | · | · | · |
| Chunks-first, not word-list first | ✓ | · | · | · | · |
| Free forever tier | ✓ | · | · | ✓ | · |
| Works fully offline | ✓ | · | · | · | · |
Pricing
Free forever. No card. No countdown.
The DET itself costs $59. Cool Mate is free. The free tier never expires. Pro unlocks unlimited daily practice and offline mode, useful in the week before your test.
Pro is optional. It exists for the week before your test.
Questions
DET candidates ask these first.
Train daily. Test from home. Move on with your life.
Free forever on iPhone, Android, Apple Watch, and Telegram. Built for DET candidates who want their hour to count.
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