Adjectives describe a noun or pronoun. They usually appear immediately before the word they describe. They answer the questions "Which one?", "What kind?", and "How many?"
For example: shy, sleepy, cute, famous, historic, three, young, old, good, bad, green, blue, funny, loud, cold, sick, proud, warm, this, that
Here's some sentences using adjectives (the adjectives are highlighted):
1. The brown dog slept until Tuesday.
(this uses the question "which one?" Which dog slept until Tuesday? the BROWN dog)
2. The cold and wet snow was all over Suzzy's jacket.
("What kind" of snow was on Suzzy's jacket? COLD and WET snow. Which jacket was it? SUZZY'S)
3. A big, red truck is stuck in the muddy road.
(Which truck? the BIG, RED one. "What kind" of road is it? a MUDDY road)
4. Four people went to the small meeting.
("How many" people went to the meeting? FOUR. "What kind" of meeting was it? a SMALL meeting)
All of these highlighted words describe something. They tell you more about the word they modify. Without them, sentences would be boring and wouldn't give you a good description or picture of what's going on.
For example, if sentence 3 were written without adjectives, it would say "A truck is stuck in the road." Without saying the truck is big and red and that the road is muddy, the sentence lacks interest and is rather boring. That's why the sentence "A big, red truck is stuck in the muddy road" is much better.
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