I try to understand _____ that prevents Mary from attending

I try to understand _____ that prevents Mary from attending I try to understand ------that prevents so many people from When I try to understand —— that prevents so many Americans When I try to understand __________that prevents children fr when I try to understand___it is that prevents so many 1道高中英语单选.I just don`t understand _____ that prevents so many I try and try to understand I try to make him understand that I am not interested in him I will be try to understand and xiwangh you.I hoped that you 1.When I try to find out ______that prevents so many people 谁能帮我解释下这个为什么选C阿I just don't understand (. )that prevents so 求翻译 Try to understand that my time is