Here is the line.
Here I am.
Why can't we hold the party here?
I'm not going out, I'm going to stay here.
I am not a grammar expert so this is a personal opinion. I think it is a sentence. Consider "Here's Tom" or "Here's the bus". They are sentences. Tom is here; the bus is here. Here's why means 'why is here', or 'this [here] is the reason [why]. It is not a particularly good sentence mind you, but it is a sentence.
This here is a sentence with 'get' in it.
An example of a declarative sentence beginning with "here": Here is your dog.
You can sit here. What is the naming part of the sentance?
No. A sentence must contain a subject and a verb. "Here's why" does not have a subject or a verb.
Here is a sentence with the word kilogram.
Here are your keys.
HERE I am! or When did you get HERE
you
here i am
Here is a sentence with adverse in it.
Type your answer here... sentence on clamber