翻译答案：
87. difficulty (in) keeping up with his classmates
88. wouldn’t have been caught by the rain
89. more likely to put on weight
90. What many people don’t realize
91. closely related to the lack of exercise
87. difficulty (in) keeping up with his classmates
88. wouldn’t have been caught by the rain
89. more likely to put on weight
90. What many people don’t realize
91. closely related to the lack of exercise
