Mistakes with HERE AND THERE

When we talk about places and location, use " here' and " there".  Here and there usually come after subject, or at the end of the sentence.
Examples:

I like Vietnam because the people here are always polite.
The weather there is beautiful
The weather is beautiful there.

Here and there at the beginning of a sentence when we introduce something.
For example: 

Here's the most important thing.
Here's my favourite thing in the world.

There's Jack
Only use " in here" and " in there" in one situation that's when two people are talking together directly and see that something contains something else.

For examples:

There's Whisky in here (in bottle)
My girlfriend is sleeping in there ( that room)