How would you describe these : declarative sentences and exclamatory sentences ?
also can you give some examples

Declarative sentence is just making a simple statement. It always ends with a period.
For example: I love you.
In this sentence all you're doing is just simply stating you love someone.

On the other hand exclamatory sentences emphasizes a statement. It needs to said with strong emotions. It always ends with an exclamation mark. That you know when a sentence needs to be said differently.
For example: I love you!
I would have to say this sentence with energy and excitement within me because it has an exclamation mark at the end of it.

Hey There!! ~

The answer to this is: Question: Which sentence is punctuated correctly?

Options:

 Our class is learning, about plant cells and Reza’s class, is learning about animal cells. Our class, is learning about plant cells and Reza’s class, is learning about animal cells. Our class is learning about plant cells and Reza’s class is learning about animal cells.   Our class is learning about plant cells, and Reza’s class is learning about animal cells.                                                                                                     The correct answer is:                                                                    Our class is learning about plant cells, and Reza's class is learning about animal cells. When a conjunction joins two independent clauses, a comma is needed before the conjunction. In the answer chosen, we can observe that it uses a comma before the conjunction ''and,'' which is linking two independent clauses. This is the correct form to use the comma.  

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