Answer:
1. A month ago, our music teacher introduced my sister and me to opera. - Past Tense
2. Opera is a form that combines music and drama into one production. - Present Tense
3. That combination suits my sister and me perfectly. - Present Tense
4. Last week we attended a light opera by Gilbert and Sullivan. - Past Tense
5. Every day that week, the show started precisely on time. - Past Tense
6. However, we arrived late because of bus delays. - Past Tense
7. After the show, we always purchase tickets for tomorrow's opera. - Present Tense
8. Yesterday a reviewer compared the lead performer with Caruso. - Past Tense
9. Enrico Caruso lived at the beginning of the twentieth century. - Past Tense
10. In his lifetime, he appeared in many operas throughout the world. - Past Tense
Step-by-step explanation:
We use the Present Tense to refer to the action which occurs in Present, to some habitual actions and general facts. In these examples, the use of the Present Tense to talk about some general facts or habits from the life of the two girls, whose teacher took them to the opera.
On the other hand, we use the Past Tense to talk about actions that took place in the past. In these examples, the use of the Past Tense is accompanied by the use of the following constructions: last week, every day that week, a month ago, etc.