freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../basic-javascript/concatenating-strings-with-...

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---
id: 56533eb9ac21ba0edf2244b8
title: Concatenating Strings with the Plus Equals Operator
challengeType: 1
videoUrl: 'https://scrimba.com/c/cbQmmC4'
forumTopicId: 16803
---
## Description
<section id='description'>
We can also use the <code>+=</code> operator to <dfn>concatenate</dfn> a string onto the end of an existing string variable. This can be very helpful to break a long string over several lines.
<strong>Note</strong><br>Watch out for spaces. Concatenation does not add spaces between concatenated strings, so you'll need to add them yourself.
</section>
## Instructions
<section id='instructions'>
Build <code>myStr</code> over several lines by concatenating these two strings: <code>"This is the first sentence. "</code> and <code>"This is the second sentence."</code> using the <code>+=</code> operator. Use the <code>+=</code> operator similar to how it is shown in the editor. Start by assigning the first string to <code>myStr</code>, then add on the second string.
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: <code>myStr</code> should have a value of <code>This is the first sentence. This is the second sentence.</code>
testString: assert(myStr === "This is the first sentence. This is the second sentence.");
- text: You should use the <code>+=</code> operator to build <code>myStr</code>.
testString: assert(code.match(/\w\s*\+=\s*["']/g).length > 1 && code.match(/\w\s*\=\s*["']/g).length > 1);
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
// Example
var ourStr = "I come first. ";
ourStr += "I come second.";
// Only change code below this line
var myStr;
```
</div>
### After Test
<div id='js-teardown'>
```js
(function(){
if(typeof myStr === 'string') {
return 'myStr = "' + myStr + '"';
} else {
return 'myStr is not a string';
}
})();
```
</div>
</section>
## Solution
<section id='solution'>
```js
var ourStr = "I come first. ";
ourStr += "I come second.";
var myStr = "This is the first sentence. ";
myStr += "This is the second sentence.";
```
</section>