为我们日常生活增添了情趣 add much spice / flavor to our daily life
Scientists do not know why dinosaurs became extinct, but some theories postulate that changers in geography, climate, and sea levels were responsible. 科学家不知道恐龙为何绝种了，但是一些理论推断是地理，气候和海平面的变化造成的。
中小学各科1对1家教辅导
天津大学生家教的价格是多少