The past continuous tense is used to describe actions that were happening or in progress at a specific time in the past. It is formed by using the past form of the verb “to be” (was or were) followed by the verb and adding “-ing.” For example, “He was reading a book.” In the negative form, we add “not” after was or were, as in “They weren’t watching TV.” In the question form, we begin with “Was” or “Were,” followed by the subject and the verb + ing, such as “Was she studying for her exams?” Common time words used with this tense are when, while, and as. We use when to show that one action interrupted another, and while or as to describe two actions happening at the same time in the past.