បញ្ហា 4ឆ្លើយតបខ្លីWhat had you been doing when the power went out in the past perfect continuous tense?Reading
បញ្ហា 7ឆ្លើយតបខ្លីWhat had the team accomplished by the end of the season in the past perfect tense?Championship
បញ្ហា 9ឆ្លើយតបខ្លីWhat had you been learning before the test in the past perfect continuous tense?Math
បញ្ហា 10ឆ្លើយតបខ្លីWhich famous scientist developed the theory of relativity in the past simple tense?Einstein