1 . During our ________ (闲暇)time, there’s nothing we like more than to sit back with the rest of the crew and watch our remarkable planet to go by, taking pictures for our family and friends back home. （根据汉语提示单词拼写）

2 . Considering these negative effects low gravity has on the human body, we ________ (严格要求)ourselves to do at least two hours of exercise everyday. （根据汉语提示单词拼写）

3 . In the ________ (情况) where new equipment needs testing, scientific experiments need monitoring, or the space station needs repairing, it's time for a spacewalk. （根据汉语提示单词拼写）