题目

    When we are unfamiliar with something，we may feel nervous and fearful．The assistance of others is a good way to help us pull through．    I write for a big newspaper, and I wanted to write a story about parachute jumping．To make it a realistic as well as exciting story，I decided that I first had to make a jump myself． Unfortunately，I am not good at any sports of any kind，let alone parachute jumping．    My friend Mr. Smith was willing to give me a hand．He took me to a ground school．The first day’s training included several hours of instruction but not my firs下列对现象解释合理的是A．铝具有良好的抗腐蚀性能，是因为它的化学性质很活泼B．水墨画可长时间保存不变色是因为碳的化学性质在常温下不活泼C．氧氧化钠需要密封保存是因为它会与空气中的氧气反应D．“酒香不怕巷子深”是因为分子间有间隔