When I went to college, Mom did all the writing. He just sent checks and a little note about how great his lawn looked now that I wasn’t playing football on it.
备注:now that(既然/因为/由于)为连词,引导原因状语从句,用来解释how great his lawn looked 的原因。即用来说明对已经发生的事情的原因。即草坪看起来时多么好是因为我没有在(草坪)上面踢足球了。