Problem: Sentence1: You never understand what I mean!
Sentence2: Happiness means everything.
Q: Does the term mean mean the same thing in both these sentences?

Answer: different meanings

Problem: Sentence1: Our advertisements reach millions.
Sentence2: His hand reaches the river.
Q: Does the term reach mean the same thing in both these sentences?

Answer: different meanings

Problem: Sentence1: He wrote a letter of apology to the hostess.
Sentence2: The CEO made a public apology for the scandal, and promised full cooperation with the authorities.
Q: Does the term apology mean the same thing in both these sentences?

Answer: the same meaning

Problem: Sentence1: All you ever do is surf the Internet.
Sentence2: A 'B' grade doesn't suffice to get me into medical school.
Q: Does the term do mean the same thing in both these sentences?

Answer:
different meanings