Lu Yi, one of your best friends, is injured in a car accident. Write a letter to him to 1) express your reaction, and 2) suggest a safer way to travel in urban areas. You should write about 100 words on ANSWER SHEET 2. Do not sign your own name at the end of the letter. Use "Li Ming" instead. You do not need to write the address. (10 points)

A. 灭活骨细胞膜的腺苷酸环化酶
B. 促进由骨骼游离钙离子
C. 促进由骨骼游离磷离子
D. 阻滞由骨骼游离钙离子
E. 阻滞由骨骼游离镁离子

A. have been
B. has been
C. are
D. had been

A. a baby dinosaur looks like a bird
B. T-rex is a kind of dinosaur figure familiar to kids
C. living feathered dinosaurs can still be found in certain parts of the world
D. scientists understand precisely how and why feathers first arose

A. to help dinosaurs fly
B. to keep dinosaurs warm
C. to distract predators
D. a mystery