My favorite part of speech in Japanese is the i-adjective.

Mostly because using i-adjectives is one of the easiest ways to make one-word sentences.

Like these gems:

(Note: In each of these translations, I'm including subjects like "this," "it," "that," etc. In real life, these would be inferred from context. So in some cases, the English would be "it," and in others it might be "this," "that," etc. It just depends on the situation.)

寒い！
さむい！
It's so cold!
Literally: "cold!"

冷たい！
つめたい！
This is so cold.
Literally: "cold!"
Note: If you can touch something (e.g. water; ice; someone's hand), use 冷たい. If it's just air (e.g. the temperature of a room, outside, etc.), use 寒い(さむい)."

キモい！
きもい！
That's disgusting!
Literally: "gross!"
Note: Girls like to say this about guys that creep them out.

眠い！
ねむい！
I'm so tired!
Literally: "sleepy!"

美味い！
うまい！
This is delicious!
Literally: "delicious!"
Note: Writing this only in hiragana, as うまい, is also quite common. In different contexts, 上手い（うまい）can also mean "skilled." So sometimes 美味い（うまい）is 美味しい（おいしい // tasty; delicious）and sometimes 上手い（うまい）is 上手（じょうず // skilled; good at）."

まずい！
This is disgusting!
Literally: "unpleasant (taste)!"
Note: This is usually used for food. But you can also say まずい if you find yourself caught in a tough situation--for example, if you're on a first date, and the sink in the bathroom sprays water all over your crotch.

安い！
やすい！
That's so cheap!
Literally: "cheap!"

怖い！
こわい！
That's so scary. // I'm scared.
Literally: "scary!"
Note: The fact that 怖い can mean both "It is scary" and "I am scared" has caused me lots of confusion in the past... as has explaining this difference when teaching English.

弱い！
よわい！
He's so weak!
Literally: "weak!"

固い！
かたい！
It's so hard!
Literally: "hard!"

速い！
はやい！
She's so fast!
Literally: "fast!"

汚い！
きたない！
It's so dirty!
Literally: "dirty!"

めんどくさい！
This is such a hassle!
Literally: "bothersome!"

---

Super-Duper Level-Up Time

You'll notice that all of those sentences above have exclamation marks. So they're pretty strong statements. That's why I use words like "so" rather often in the translation.

But we can make all of these Japanese sentences stronger by dropping the い at the end, then cutting the word short right at the last kana.

For example, we had:

寒い！
さむい！
It's so cold!
Literally: "cold!"

We could change 寒い（さむい）to 寒っ（さむっ）, and the emphasis would be stronger.

Here, the little っ just indicates that you should cut off your breath right at the end of む.
Further, you should stress the final kana. So you don't just say samu!; you saysaMU!

It's best to practice this sound with a native speaker, so if you have one around, yeah... Also, practicing this Japanese is awesome. It's fun for native speakers, too.

Below, you'll see that I haven't changed any of the translations, but you should just assume that the emphasis is higher for the versions with っ. Additionally--though I think maybe this goes without saying--this is pretty casual language. Don't use it if you're having tea with the emperor or something.

寒い　→　寒っ！
さむい　→　さむっ！
It's so cold!
Literally: "cold!"

冷たい　→　冷たっ！
つめたい　→　つめたっ！
This is so cold.
Literally: "cold!"

キモい　→　キモッ！
きもい　→　きもっ！
That's disgusting!
Literally: "gross!"

眠い　→　眠っ！
ねむい　→　ねむっ！
I'm so tired!
Literally: "sleepy!"

美味い　→　うまっ！
うまい　→　うまっ！
This is delicious!
Literally: "delicious!"

まずい　→　まずっ！
This is disgusting!
Literally: "unpleasant (taste)!"

安い　→　安っ！
やすい　→　やすっ！
That's so cheap!
Literally: "cheap!"

怖い　→　怖っ！
こわい　→　こわっ！
That's so scary. // I'm scared.
Literally: "scary!"

弱い　→　弱っ！
よわい　→　よわっ！
He's so weak!
Literally: "weak!"

固い　→　固っ！
かたい　→　かたっ！
It's so hard!
Literally: "hard!"

速い　→　速っ！
はやい　→　はやっ！
She's so fast!
Literally: "fast!"

汚い　→　汚っ！
きたない　→　きたなっ！
It's so dirty!
Literally: "dirty!"

めんどくさい　→　めんどくさっ！
This is such a hassle!
Literally: "bothersome!"

In the next lessons, we're going to look at a very similar, though entirely different way of emphasizing i-adjectives.

Get excited.