第2题: [单项选择]There has been a ______ increase of complaint about the matter because of misunderstanding. A. regretting B. regretted C. regretful D. regrettable 参考答案:D 答案解析:单词regrettable:可悲的;可惜的;抱歉的。指使人感到遗憾的、值得可惜的意思。单词regretting是正在使人遗憾的或者人们正在遗憾的。单词regretful表示感到遗憾可惜的意思。单词re