完型填空：

67. income

68. mostly

69. Besides

70. trend

71. particularly

72. while

73. slipping

74. if

75. larger

76. liable to

77. unique

78. over

79. decay

80. relieved

81. widening

82. massive

83. cycles

84. or

85. predicts

86. likely

翻译：

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 evercise