Here are the closest meaning answers for the underlined words in the sentences:

14. Many streets in the centre of Ha Noi **were flooded** by prolonged heavy rain last month.
- **A. were flooded**

15. It’s believed that ASEAN plays an important role in maintaining and **promoting** regional peace.
- **A. boosting**

16. Experts in climatology and other scientists are becoming extremely **concerned** about the changes to our climate which are taking place.
- **C. aware**

17. There will be a **decrease** in the number of compulsory subjects for high school students attending the final exam in 2025.
- **A. increase** (opposite meaning)

18. The government project aims to **promote** health services in disadvantaged areas.
- **B. boost**

19. The doctor said that she was doing **good progress**.
- **D. progress**

20. Some people still think that our **natural** resources can never be **depleted**.
- **A. prevent** (opposite meaning)

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