---
title: Declare a Read-Only Variable with the const Keyword
---
![](//discourse-user-assets.s3.amazonaws.com/original/2X/3/3c8584a085a0deaea66b3400e6321eeadab552a2.jpg)
![:triangular_flag_on_post:](https://forum.freecodecamp.com/images/emoji/emoji_one/triangular_flag_on_post.png?v=3 ":triangular_flag_on_post:") Remember to use **`Read-Search-Ask`** if you get stuck. Try to pair program ![:busts_in_silhouette:](https://forum.freecodecamp.com/images/emoji/emoji_one/busts_in_silhouette.png?v=3 ":busts_in_silhouette:") and write your own code ![:pencil:](https://forum.freecodecamp.com/images/emoji/emoji_one/pencil.png?v=3 ":pencil:")
### Problem Explanation:
Change all the variables to `let` or `const` and rename `sentence`.
## ![:speech_balloon:](https://forum.freecodecamp.com/images/emoji/emoji_one/speech_balloon.png?v=3 ":speech_balloon:") Hint: 1
* Replace `var` for string with read-only `const`.
> _try to solve the problem now_
## ![:speech_balloon:](https://forum.freecodecamp.com/images/emoji/emoji_one/speech_balloon.png?v=3 ":speech_balloon:") Hint: 1
* Replace `var` in `for` loop to `let`.
> _try to solve the problem now_
## ![:speech_balloon:](https://forum.freecodecamp.com/images/emoji/emoji_one/speech_balloon.png?v=3 ":speech_balloon:") Hint: 1
* Common convention is to name `const` variables with ALL CAPS.
> _try to solve the problem now_
## Spoiler Alert!
![warning sign](//discourse-user-assets.s3.amazonaws.com/original/2X/2/2d6c412a50797771301e7ceabd554cef4edcd74d.gif)
**Solution ahead!**
## ![:beginner:](https://forum.freecodecamp.com/images/emoji/emoji_one/beginner.png?v=3 ":beginner:") Basic Code Solution:
```javascript
function printManyTimes(str) {
"use strict";
const SENTENCE = str + " is cool!";
for(let i = 0; i < str.length; i+=2) {
console.log(SENTENCE);
}
}
printManyTimes("freeCodeCamp");
```
![:rocket:](https://forum.freecodecamp.com/images/emoji/emoji_one/rocket.png?v=3 ":rocket:") Run Code
# Code Explanation:
By using `const` on `sentence` we can make it read-only and by using `let` on `i` inside the for loop we can avoid using `var` all together. For added code clarity we can also change `sentence` to `SENTENCE` to show that it is a constant.
#### Relevant Links
* const
* let
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