Complete the sentences using the verbs in brackets. Use the past perfect continuous or simple.
1. The detectives could see it _____ (rain) by the wet grass.
2. Jack ____ (refuse) to stay any longer so we'd all had to leave.
3. Caroline guessed James _____ (take) the car because the keys were gone.
4. Sarah ____ (date) Robert for years when they broke up.
5. Lu couldn't remember if she ____ (turn off) the gas before she left.