I think that he must c<span>elebrate all he has to look forward to as a fifty year old. This is because he achieved this year and he is still living. He must be thankful that he lived for 50 years and I guess that the best way that he can show his gratitude is to celebrate it.</span>
The independant clause mean the simple subject which says that you can read a part of a sentence that makes a lot of sense. So in this sentence "Since you are writing a poem, how will you use metaphors?"
The dependent clause is the one that makes no sense while being alone.
In this sentence the dependent clause is Since you are writing a poem.
It makes no sense all alone in one sentence.
Now for the actual question answer is the independent clause.
The independent clause is how will you use metaphors?
I think that is the independent clause because it really makes sense even though it's a part of the question.
Answer: Objective
Explanation: Because you have to restate the facts you just presented and show you know what your doing/talking about.
Hope this helps (: