17. The Red List has been introduced to... A. lift B.grow 18. When he came, I A. cooked in the kitchen. people's awareness of conservation needs D.raise C. rise D. was cooking to protect our health. B. am cooking C. has cooked 19. A face mask whenever we go out of the house during the pandemic A. must be wornB. must wearC. must wornD. must not be worn in 1970 by my grandfather. 20. This house A. built B. was built C. was build D. has built meaning to the underlined word(s) in each of the following