I would replace "learn" with "study". A person "studies hard", and does not "learn hard." The next point is a matter of preference. I like "the more you will improve" better than "the more you can improve." The former is a direct cause-effect scenario (the more you do X, the more you will get Y). Saying "the more you can improve," on the other hand, leaves me with the sense that after studying hard, there is only a possibility that you will improve. Of course, maybe this is true! So changing "can" to "will" is optional. So I propose: "The harder you study English, the more you will improve." Otherwise it is great!

もうこれ以上はないぐらいに is a partial sentence that needs some sort of adjectival phrase to modify. It means something like "couldn't be Y", where Y is an adjective in comparative form. Literally, it means, "it is almost like（くらいに） there is nothing（ない） above （以上）this（これ)", so the phrase as a whole acts like a modifier to make a superlative. Examples: これ以上ないくらい幸せ = (I) couldn't be happier! = 最高に幸せ これ以上ないくらい悪い = (This) couldn't be worse! = 最悪 So to figure out what the full sentence means, we will have to look at the phrase before or after もうこれ以上ないくらいに。

Question 1: Given that our lower jaw connects to the upper jaw at two points, it may be more anatomically correct to say "hinges." However, this is not a medical textbook. It is a work of fiction and does not have to be medically precise. Moreover, from outward appearances, we generally perceive ourselves as having one lower jaw (and one mouth) - as opposed to having two knees and two elbows. So perhaps referring to the jaw joint as one HINGE instead of two HINGES just sounds more natural...? Having said all the above, there would be nothing wrong if the plural form "hinges" were used instead of the singular form. But purely for the phonetic flow of the passage, I would also probably use "hinge" instead of "hinges." Question 2: Yes. There is no reason, given the context, to believe that it was merely an "explosive sound." Bonus question 3: Wait, Barbie is a he?

Jemand is the subject. The sentence, I believe, means: "Anyone who has made a hasty escape will not be found where he is sought." 任何一個落跑的人，不會在他人尋找他的地方 被尋獲。

兴奋 means "excited"/"stimulated" and generally in a positive way. So if you are looking forward to something, 兴奋describes that state of mind more closely. Examples: 消息传来，人人为之兴奋。As the news arrived, people got really excited. 这是一个令人兴奋的场合。This is a very exciting occasion. 我们都为这消息感到兴奋。We were all excited by the news. 麝香被用作香料和兴奋剂。Musk is used as a fragrance and a stimulant (this shows how 兴奋 is closely related to "excite," "stimulate"). On the other hand, 激动 is closer to "emotional." Examples: 他一辩论起来就十分激动。He gets very emotional when he starts arguing. 潘是个非常容易激动的人。Pan is the type of person who easily gets emotional. 我容易激动，却不爱报复。I get emotional easily, but I do not like to seek revenge. 这段旧梦重温使我很激动。This rekindled old dream made me very emotional. Hope this helped!

When X "tends to" do Y, it means that X is likely to do Y. Here, the sentence means that "the profits from ecotourism are in general higher than the profits from mass tourism." 用中文說明的話，"生態旅遊的獲利通常比大眾旅遊的獲利來得高“

It's "set off for" Beijing. But you can say "I'm off to Beijing" if you leave out the "set". :)

The miracle is that these astonishing aristocratic danses, which derive from military parades and take place before a temple, which reflect not only the unfathomable pride of the ruling classes but also the mysticism surrounding the imperial and royal dynasty, contain such startling beauty.