Communication of Proposal:
The communication of a proposal refers to the process of making an offer or a proposition to someone with the intention of entering into a contract. It is a crucial step in the formation of a contract and involves the expression of willingness to do or abstain from doing something in exchange for something else. The communication of a proposal can be complete when it is made to the person to whom it is intended or their authorized agent.

Acceptance:
Acceptance is the positive response to a proposal, indicating the willingness to enter into a contract. It is the offeree's agreement to the terms and conditions presented in the proposal. Acceptance can be communicated either verbally, in writing, or through conduct, depending on the nature of the contract and the intention of the parties involved. For acceptance to be valid, it must be unconditional, absolute, and in conformity with the terms of the proposal.

Revocation:
Revocation refers to the act of withdrawing or retracting an offer before it is accepted. It is the right of the offeror to cancel or revoke the proposal at any time before it is accepted by the offeree. Revocation can be communicated through any reasonable means, such as oral or written communication, as long as it reaches the offeree before acceptance. Once the offeree receives the revocation, the offer is effectively terminated and cannot be accepted.

Completion of Communication:
The communication of a proposal, acceptance, and revocation is considered complete when the respective parties receive the communication. Here are the details of completion for each step:

1. Communication of Proposal:
- Complete when the proposal is made to the person intended or their authorized agent.
- The offeror must ensure that the proposal reaches the offeree or their authorized agent.
- If the proposal is sent by post, it is considered complete when it is put into the post office.
- If the proposal is made through electronic communication, it is complete when it enters the recipient's information system.

2. Acceptance:
- Complete when the offeree communicates their acceptance to the offeror.
- Acceptance can be communicated through various means, such as in person, by post, email, or any other agreed-upon method.
- If the acceptance is sent by post, it is complete when it is posted.
- If acceptance is made through electronic communication, it is complete when it enters the recipient's information system.

3. Revocation:
- Complete when the offeree receives the revocation from the offeror.
- The revocation can be communicated through any reasonable means, such as in person, by post, email, or any other agreed-upon method.
- If revocation is sent by post, it is complete when it is posted.
- If revocation is made through electronic communication, it is complete when it enters the recipient's information system.

In conclusion, the communication of a proposal, acceptance, and revocation is considered complete when the respective parties receive the communication. It is essential for the parties involved to ensure that their communications reach the intended recipients to avoid any misunderstandings or disputes regarding the formation of a contract.