When you describe a noun with multiple adjectives, you need a comma between the adjectives. Look at these sentence examples:
The Amazon driver delivered a big, heavy box to our front door.
The word box is described with two adjectives: big and heavy. The box is big. The box is heavy.
When we use two adjectives in a row like that, we need to separate the two adjectives with a comma.
It’s a big, heavy box.
Here are more examples:
Sam woke up to a dark, rainy morning.
The fast, sleek racecar sped around the track.
I wrinkled my nose at the damp, musty smell in the basement.
In each of these examples, we could use the adjectives separately and the sentence would still make sense.
Sam woke up to a dark morning. Sam woke up to a rainy morning.
The fast racecar sped around the track. The sleek racecar sped around the track.
We put a comma between the two adjectives when we can separate them out like this and the sentence still makes sense.
When using two adjectives to describe a noun, insert a comma between the two adjectives.
▶Now you try it. Place a comma in this sentence: A noisy boisterous crowd filled the gymnasium. Did you place the comma between the two adjectives? Good for you!