A. designs
Đáp án C
Giải thích: rút gọn mệnh đề quan hệ dạng chủ động
The classroom windows and sliding doors (5) ________ open to the outside most of the year. The roof is a big, wooden circle. Children love to play and run on it.
So for all of you lefties, leftie- loving righties, and ambidextrous folks out there - it’s time to brush up on your left-handed knowledge and help ________(35) an end to leftie discrimination once and for all