21.A确认该题答案的信息为:“As layperson totally green about comic book collecting would allow someone like me to basically start a collection from the very beginning. ".. are invaluable to a beginner.22.D确认该题答案的信息为: found the pieces on the Artists particularly interesting.以及信的第2段内容。23.D确认该题答案的信息为:“ only wish that had had this information40 years agowish后接宾语从句时表示说话人认为不能实现的愿望24.B确认该题答案的信息为:第3段“My students began their investigations and, after40 minutes,they shared their discoveries.