Answer:
1. Finished
2. who
3. spending
4. Don't
5. before
Step-by-step explanation:
1. The word "yesterday" indicates that the sentence is in past tense form. The past tense form of "finish" is finished.
2. Who refers to a person, when refers to time, and which refers to a choice of something.
3. Spending is the present participle form of "spend." (Present participles end in "ing")
4. Don't means do not. Did would be appropriate if the sentence was asking a question. Do would contradict the meaning of the sentence, and Does just doesn't make sense.
5. Before is the best choice because "before" means that you need to do a certain thing first.