Here are the answers for your sentences:

36. **It was such an interesting English book that I have read it many times.**

37. **If adults read English books regularly, they can improve their vocabulary.**

38. **She wishes she had the opportunity to study abroad in an English-speaking country.**

39. **I think English is the most useful language for the future.**

40. **Despite the fact that there are different accents in English, it is widely understood.**

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