Passe compose and Imparfait usage

Which tense should you use in this situation?
If something only ever happened one time: "She ate the bug."

Which tense should you use in this situation?
If something happened over and over again: "Every Saturday, they went to the gym."

Which tense should you use in this situation?
If something lasted for so long you can't keep track of how long it lasted: "For years, I practiced the guitar."

Which tense should you use in this situation?
For a physical description: "The rabbits were white and had long ears."

Which tense should you use in this situation?
For a psychological description: "She was upset about the accident."

Which tense should you use in this situation?
Almost always with the verb etre

Which tense should you use in this situation? When you know the specific date or time something happened: "On November 16th, 1940, he joined the Marines."

Which tense should you use in this situation?
When an action happened instantaneously: "Suddenly, the class burst into song."

Which tense should you use in this situation?
When something was background information: "That night, it was raining and storm clouds loomed over the land."

Which tense should you use in this sentence:
She was beautiful