6、sagewecaninferthat________.A.spaceflightisstilldangerousB.spaceflightissafeC.noonewantstotravelintospaceagainD.thespaceisn'tworthexploring【答案】 A 阅读P58-P59教材课文,在空白处填入适当的内容(1个单词)或括号内单词的正确形式NeilArmstrongfirstsetfootontheMoonbackon21stJuly,1969,1.________wasonesmallstepforman,butonegia