Hi Professor Hayes,
If someone opens a corporation, then enters into a partnership to carry out the business, does that mean that the corporation becomes part of the partnership or the corporation will be a separate entity?
First a corporation, once formed, will continue to exist and be a corporation until the end of eternity unless dissolved by the state. A partnership is the same except that it ends when the agreement ends (or eternity, whichever occurs first).
If a corporation enters into a partnership with someone else, a person, a corp or another partnership, then the corp is a partner in the partnership. The corp has its assets and business, the partnership has its assets and business. Assume that Apple and Microsoft decide to build a new computer, they could form a new corporation to do that (which issue stock to each) or just agree to do it together which would create a partnership (sometimes called a joint venture). The partnership is created by the agreement to create the thing. IT has two partners.
You and I could agree to start a sports bar. We each form corps, mine is ProfHayes, Inc. Yours is “Student, Inc. The two corps then agree to buy or build a sports bar. That agreement creates a partnership which would then own and operate the sports bar. If the partnership agreement says the partners get x dollars per month, that would go to the two corps. The BOD of each corp would then decide to declare dividends or invest the money or whatever. The partners are liable for the debts of the partnership but that means the two corps, not you and I personally.