根据下列句子及所给单词的首字母，在答题纸上按题号写出各单词正确的完全形式（每空限写一词）。

81. I r______ to tell you that I am unable to accept your kind invitation.

82. The couple are always a______ with each other about money.

83. We want our son to have an education that will e______ him for later life.

84. When we visited my old family home, memory came c______ in.

85. They r______ chemical fertilizers in their farming but used more organic fertilizer to keep the soil natural.

86. The classic single Hey Jude reached an even wider a______ after it was performed by Paul McCartney at the opening ceremony of the London Olympics.

87. They bought some cars from the developed countries with the dollars earned by e______ wheat, corn and rice.

88. As we all know, there is a strong c______ between smoking and heart disease.

89. The government provided coats, quilts, carpets to the school to help r______ the students of cold.

90. I thought I was quite a good artist, but your painting puts mine in the s______.