The Imperfect Tense
The Imperfect tense shows a repeated, ongoing, or continuous past action. It is kind of like background scenery. It shows what was happening for a period of time.
These examples show that the action took place over a period of time versus one single incident in the past. To form the imperfect tense in Latin, follow these steps.
As you can see, every ending has -ba-. This is called the tense indicator. The present tense doesn't have one, the future tense uses -bi-, and the imperfect uses -ba-. Also, notice that the -o is no longer used to show the 1st person singular. Here, instead, you use -m. This is important. If the -o were used, it would make the -a- disappear, and then we wouldn't be able to tell the difference between that and the future tense.
The verb laudo, laudare, laudavi = to praise in the imperfect tense.
That is all there is to it.