"Have the chance of" or "have a chance of"

Question

Which one is correct?

• Once you have a chance of reviewing the document, let me know what you think.
• Once you have the chance of reviewing the document, let me know what you think.

Answer 1

Which one is correct?

Neither! It should be

Once you have a chance to review the document, let me know what you think.

The answer to to your underlying question — why “a” versus “the” — is that “the” suggests there is only one opportunity. This is commonly used in the negative:

“I never had the chance to meet George H. W. Bush.”

but you might say

“I have never had a chance to meet George W. Bush.”

(The difference being that George H. W. Bush has joined the choir invisible, but his son George W. Bush is still among the living, as of August 2024 at least, and still available for meeting.)

I don’t think a native English speaker would notice the switch between “a” and “the”, whatever the circumstances, but he would certainly hear “chance of reviewing” as awkward and non-standard.

Answer 2

I. Meaning of OP's two sentence.
Both sentences are grammatically correct, but there's a subtle difference:

1. "Once you have a chance of reviewing the document...".
   This implies that you might or might not get the opportunity to review the document. The phrase "a chance of" suggests uncertainty or possibility.
2. "Once you have the chance of reviewing the document...".
   This implies that you will definitely get the opportunity to review the document. The phrase "the chance of" suggests a more definite or guaranteed opportunity.

II. How to say "should review or must review"?.
The sentences imply that the person will review the document, but they don't directly instruct them to do so. If you want to explicitly instruct someone to review the document, you could rephrase the sentences to something like:

"Please review the document and let me know what you think.".
Or:
"Once you've reviewed the document, please share your thoughts with me."

III. OP's sentences are polite..
Direct instructions like "Please review the document" can come across as somewhat imperative or even bossy, especially in formal or professional communication.

The original sentences ("Once you have a chance...") are more polite and courteous. gentle tone.

By using these softer phrases, you're showing respect for the person's time and opinions, which is particularly important in professional or formal communication.