19. I haven’t heard from her for many years.
→ The last time I heard from her was many years ago.

Explanation: The sentence is restructured to emphasize the last time the speaker had contact with "her" in the past.
Dịch: Lần cuối cùng tôi nghe tin từ cô ấy là cách đây nhiều năm.

20. The children haven’t been taken to the park since 2012.
→ The last time the children were taken to the park was in 2012.

Explanation: This transformation uses "the last time" to specify the year the children were last taken to the park.
Dịch: Lần cuối bọn trẻ được đưa đến công viên là năm 2012.

21. This is not the first time we have visited this city.
→ This is not our first visit to this city.

Explanation: "Not the first time" is rephrased as "not our first visit" to convey the same meaning in a simpler form.
Dịch: Đây không phải lần đầu tiên chúng tôi ghé thăm thành phố này.

22. This is the second time I have seen this movie.
→ I have seen this movie twice.

Explanation: The sentence is transformed to focus on the total number of times the speaker has watched the movie.
Dịch: Tôi đã xem bộ phim này hai lần.