Problem: Sentence1: To purchase land, to purchase a house.
Sentence2: The family purchased a new car.
Q: Does the term purchase mean the same thing in both these sentences?

Answer: the same meaning

Problem: Sentence1: We had to dress quickly.
Sentence2: Can the child dress by herself?
Q: Does the term dress mean the same thing in both these sentences?

Answer: the same meaning

Problem: Sentence1: His novels always have a lot of action.
Sentence2: The United Nations must have the power to propose and organize action without being hobbled by irrelevant issues.
Q: Does the term action mean the same thing in both these sentences?

Answer: different meanings

Problem: Sentence1: I'll post the news on the bulletin board.
Sentence2: Post a sentinel in front of the door.
Q: Does the term post mean the same thing in both these sentences?

Answer:
different meanings