Поставить глаголы в правильную форму. 12. he (not/ hear) the thunder during the storm last night because he (sleep). 13. we hope that scientists (find) solutions to our most urgent problems. 14. by next decade people (create) more efficient purification equipment. 15. what geologists )? 16. there isn’t a cloud in the sky. it (be) a lovely day. 17. this time last year i (swim) in the black sea. 18. they (work) at a chemical laboratory now. 19. in 1974, scientists (not / predict) an earthquake in china. 20. they (carry out) an experiment from ten till twelve o’clock in the morning. 21. he (solve) this problem by 10 o’clock yesterday.