It is very cold　：（

It is December today!
oh…This year also finishes.
I must clean up my room！
After all I am finish without performing this time…?

It's another December day. This year will soon come to an end and it's a sign that I must clean up my room.

I am not really sure that you mean by the last sentence.

It is very cold　：（

It is December today!
oh…Before this year also is finished,
I must clean up my room!
After all this time, I am still not finished.

I'm not sure I understood your last sentence. I hope that is right, and good luck cleaning your room! :)