TOPIC: definition for those words

Can I have the definition for those words and the differences between each?

In my practice, I always use the "Past tense" after the subject word in a sentence.
For example, I send a document to"A" company and request for a confirmation to ensure the document was delivered. So, I will write a e-mail to her/his like this:-
"The supporting document will be sent to you today by courier, please confirm the receipt when you received the document "
Is it correct, please help?

Thanks a lot!

Here's your sentence corrected"
"The supporting document will be sent to you today by courier. Please would you let us know when you have received it."