I just thought I would provide some common spelling mistakes I notice from time to time, and some common misuse of words. This isn't an English lesson, but I thought it would be helpful. I am sure I missed some, and would be glad to post them if anyone wants to share.

Hear - As in listening. Can you hear me now?

Here - As in location. Are you here in the building?

Where - Where are you?
Wear - As in clothing or to adorn oneself with.
Were - Were you coming to dinner?

We’re - Contraction for - "We are" so glad you could make it.

Effect - See

Affect - Below

There - Location. Direction. There is a long line at the bank.

Their - Showing plural possession. Their deeds were hidden from sight.
They're - Contraction for - "They are" the new neighbors.

To - To go where no man has gone before.

Two - The number 2.

Too - Excess - as in Also. Can be used interchangeably. I can do that too (also)!

Know - As in knowledge present tense. I know what you are saying.

No - As an answer to a question. A command. No I don't understand.

Knew - As in kowledge past tense. He knew him well before he died.

New - As in recent, just made, fresh. This car is brand new.

Through - As in completing a process, or passing through something. He went through a tough time.

Threw - To throw a ball.

Thru - This is not a word. It is slang.

Then - referring to a point in time. Back then things were different.
Than - To be used as a comparison. I like peas rather than carrots.

You're - Contraction for "you are" as in you're a nice guy.
Your - Showing possession of. Please restrain your dog.

Effect or Affect?
Affect and effect are two words that are commonly confused.
"Affect" is usually a verb meaning "to influence".

  • The drug did not affect the disease.

"Effect" is usually a noun meaning "result".

  • The drug has many adverse side effects.

"Effect" can also be used as a verb meaning "to bring about".

  • The present government effected many positive changes.