something or someone that is difficult to understand
某事或某人很难理解 (mou shi huo mou ren hen nan li jie)
"He’s a closed book when it comes to his personal life."
"当涉及到他的个人生活时，他就像一本封闭的书。" (dang shi ji dao ta de ge ren sheng huo shi, ta jiu xiang yi ben feng bi de shu)
to organize things in a proper and efficient way
crawling on hands and knees
to take on a lot of responsibility
deeply shocked or disturbed
to focus on moving forward and not dwell on past mistakes
to confront something that scares you
