 Now let's have a look at the past continuous tense. This tense is used to indicate that a certain action was in progress at a particular time in the past. We form this positive form by using our subjects, our helping verb, or auxiliary verb to be, plus the verb plus ing form, also known as the present participle. So it results in sentences such as, he was cooking last night, or we were cooking last night. In order to form the negative sentence for the past continuous, we add the word not in between the past form of the helping verb to be and our main verb, which here is cooking. So of course we have, he was not cooking last night, and we were not cooking last night. In order to form the question for the past continuous tense, again we're going to invert our subject and our helping verb. So we start our question with was or were depending on our subjects, and we keep our present participle form of the verb, which is our main verb in the question. So was he cooking last night, or were you cooking last night?