must_know:
Dear Father,
$chool i$ really great. I am making lot$ of friend$ and $tudying very hard. With all my $tuff, I $imply ?an't think of anything I need, $o if you would like, you can ju$t $end me a card, a$ I would love to hear from you.
Love,
Your $on.
After receiving his son's letter, the father immediately replies by sending a letter back.
Dear Son,
I kNOw that astroNOmy, ecoNOmics, and oceaNOgraphy are eNOugh to keep even an hoNOr student busy. Do NOt forget that the pursuit of kNOwledge is a NOble task, and you can never study eNOugh.
Love,
Dad
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