Câu hỏi:Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.
Her sister is expert _______ growing flowers. A. with B. at C. by D. for
Expert at/ in sth: chuyên môn, thành thạo Tạm dịch: Chị gái cô là chuyên gia trồng hoa.