Làm vài giải thích ạ ----- Nội dung dịch tự động từ ảnh ----- Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
19. A. in We are tired ___ waiting the weather ___ to clear. B. are C. to D. writing
20. A recent study of 2000 species of plants and animals have suggested an answer to this question. B. have C. to D. species