Question: Here is one sentence: I will work hard to improve my grades.
Here is another sentence: John worked with Paul at finishing the task.
Does the work mean the same thing in the two sentences?

Answer: the same meaning

Question: Here is one sentence: A lot of money.
Here is another sentence: He bought a lot on the lake.
Does the lot mean the same thing in the two sentences?

Answer: different meanings

Question: Here is one sentence: The children were playing house.
Here is another sentence: She felt she had to get out of the house.
Does the house mean the same thing in the two sentences?

Answer: different meanings

Question: Here is one sentence: I know it's time.
Here is another sentence: She knew of our plan.
Does the know mean the same thing in the two sentences?

Answer:
the same meaning