This girl is beautiful. She a beautiful girl. Explain why article follow by adjective?

You're right to notice the difference! It's a bit tricky, but here's why "a beautiful girl" is correct:

* "A" is an indefinite article. It indicates that we're talking about one girl, but not a specific one. It's used with singular, countable nouns (like "girl").

* "Beautiful" is an adjective. It describes the noun "girl."

* Articles come before adjectives. This is a standard rule in English grammar. The article modifies the noun, and the adjective modifies the noun that is already modified by the article.

Here's a breakdown:

1. "A" - This tells us we're talking about one, non-specific girl.

2. "Beautiful" - This describes the girl we're talking about.

So, the complete phrase "a beautiful girl" means "one girl who is beautiful."

Important Note: While "She is a beautiful girl" is grammatically correct, it's often considered redundant. "She is beautiful" is perfectly sufficient and more concise.