I. Supply the correct form of the verbs in the brackets to complete the sentences below. (10 points) 21 Maria left college early today because she _____ (have) a dental appointment an hour ago. 22 As soon as it stops raining, we _____ (take) the dog for a walk. 23 For the past six weeks, I _____ (have) singing lessons. 24 I can't phone you at that time because I _____ (travel) on the underground. 25 As a rule, she _____ (spend) part of each summer at her parents' house. 26 His back was aching because he _____ (dig) in the garden all day. 27 When I woke up, I saw the house _____ (burn). 28 James hasn’t come here. I think he _____ (miss) the bus. 29 He is the last person _____ (know) the news. 30 They wish they _____ (own) a hotel in the future.