请判断下面四个句子中划线词所引导的从句类型。 * 1 How the whole image is then assembled and perceived is still a mystery 2 although it is the subject of current research. * 3 While studies have shown 4 that acrylamide can cause neurological damage in mice, there is no conclusive evidence5 that it causes cancer in humans. * 6 Whether you're a politician or a parent, it might be helpful to keep in mind that trying to maintain eye contact may backfire if you're trying to convince someone 7 who has a different set of beliefs than you. * A more direct finding is 8 that people 9 who scored high for negative emotions like anxiety looked at others for shorter periods of time and reported more comfortable feelings 10 when others did not look directly at them.