Read the grammar rules and choose the correct option

1. To talk about things that regularly happened in the past but are no longer true, we use
   [be used to+ V-ing| used to+ V| get used to+ V-ing].
2. To talk about things that were not our habits in the past, we use
   [didn't use to+V| be not used+to V-ing| didn't used to+V].
3. To talk about things that we are familiar with and which are a part of our lives, we use
   [be used to+ V-ing| used to+ V| get used to+ V-ing].
4. To talk about things that are new to us but we are in a process of becoming familiar with, we use
   [be used to+ V-ing| used to+ V| get used to+ V-ing].