1, Qu Yixian is a company specializing in supplementary books, and its products involve many fields such as mathematics, physics, chemistry and biology. Qu Yixian's supplementary books pay attention to the explanation of basic knowledge and problem-solving skills, and also pay attention to cultivating students' thinking ability and problem-solving ability. Spark is a company focusing on English teaching, and its products include English vocabulary, English reading and English grammar.

2. The price of Quyi line supplementary books is relatively reasonable, the question bank is updated quickly and the overall cost performance is high. Spark's supplementary books are expensive, but the question bank in them is slow to update and has a single style.