VOA慢速英语:An Introduction to Verb Tenses

aspect – n. the verb form that indicates completion, duration, or repetition of an action.

distinction – n. a difference that you can see, hear, smell, feel, etc: a noticeable difference between things or people

spontaneous – adj. done or said in a natural and often sudden way and without a lot of thought or planning

consciously – adv. done after thinking about facts and reasons carefully

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