ANSWER PART 2： 3 由 phrases for instance are: =reason 原由yuan2 you2，理由li3 you2，=due to 由于you2 yu2，=from 由第一个开始you2 di4 yi1 ge4 kai1 shi3（from the beginning），由外及里you2 wai4 ji2 li3（from outside to inside），=sincerely 由衷地you2 zhong1 de，=according to this 由此可知you2 ci3 ke3 zhi1 由in No.9 sentence =the reason, in order to=为了 in Chinese Examples: 1 他有这么做的理由/原由 He has the reason to do this. 2 由于天气的原因，飞机延后起飞了。Due to the weather reason, the departure of the flight is delayed. 3 请 由/从 第一个同学开始回答问题。Let’s start to answer these questions from the first classmate. 4 我们一起将屋子由外及里打扫的十分干净。We cleared the room from outside to inside. Actually, you just need to know one of 由’s meaning is “from”, we don’t use 由外及里 very often. 5 我由衷地感谢您的帮助。Sincerely thanks to you. 6 由此可知，他的答案是错误的。According to this, his answer is wrong. BTW, your question in No.8 sentence: Also 但是却 seems like it's repeating "however" "but". Can only one be used "但是“ or "却“ and get the same meaning. Having both does it add emphasis? A: You could only 但是 or 却, either is fine, both the meaning is “however/but”. 但是却 here is a little bit add emphasis here, but it’s have to use 但是却here.

Hi, Jun jie, the answers above are just my opinion. I hope those will help you. Kitty

ANSWER PART 1 Hi, I just saw your questions, maybe it’s not so hard to understand how to use the word 由. I will try to summarize it to you. Basically,由 have 3 ways to be used, and all of your examples contain them. 1 in a phrase 由…构成/组成=be made up of=be comprised of eg: sentence No.1. 那种昆虫的身体由一个由关节相连的硬外壳构成=关节相连的硬外壳构成了这种昆虫的身体。 No.6: Today's new frontier is comprised of the interconnected wires, routers and computers of the Net. 今天，新的边远地区由许多互相联接的线路、路由器及网络计算机组成。 =The interconnected wires, routers and computers of the Net comprised today’s new frontier. 许多互相联接的线路、路由器及网络计算机组成了今天的边界 No.7: The nation is comprised of thirteen states. 这个国家由13个州组成 = Thirteen states comprise the nation. 13个州组成了这个国家。 2 It’s a little bit harder to understand the structure: 由+主语subject + verb,but the other way of expression will help you to understand. So what you should do is realizing this structure in one sentence, and change the way of your expression. Besides, although 由 translate into English is “by”,but we should still only use 由 here for a better expression. Below are the analysis of your examples, and I will highlight the subject（主语zhu3 yu3）in blue. eg: sentence No.2: These magazines are produced by the same firm. 这些杂志都是由同一家公司出版的。 = The same firm produced these magazines. 同一家公司出版了这些杂志 No.3: The churches are ruled by men but kept alive by women. 教堂由男人统治着，但是却由女人管理着。 =Men ruled the churches, but women kept them alive. 男人们统治着教堂，但女人们却管理着它们。 No.4: The food, distributed through the U.N. World Food Program, is paid for by corporate sponsors. 这些食品由联合国世界食品计划组织负责发放，费用由赞助公司支付 = The U.N. World Food Program distributed the food, and corporate sponsors paid for the food. 联合国世界食品计划组织负责发放这些食品，而赞助公司负责支付费用。 No.5: The London Stock Exchange's SETS trading platform, which was built and is mostly operated by Andersen Consulting, crashed last month. 伦敦证券交易所采用的交易平台由安盛咨询公司设计，并主要由该公司经营。但是该平台上个月瘫痪了。 = Andersen Consulting built and operated the London Stock Exchange's SETS trading platform mostly. 安盛咨询公司设计并主要负责经营伦敦证券交易所的交易平台 No.8: Before we start playing we have to decide who will be in charge of the bank. 玩儿之前我们得决定由谁来管理这些赌本。 = Before we start playing we have to decide one thing: Who will manage the bank.我们玩之前要决定一件事：谁来管理赌本。 No.10: The next radio program will be introduced by Larry. 下一个广播节目由拉里来播报。 =Larry will introduce next radio program. 拉里负责播报 No.11: It's clear that this photo has been shot by a master. 很明显这张照片是由行家拍摄的。 =It’s clear that a master has shot this photo. 很明显一位行家拍摄了这张照片。 No.12: This situation is partly due to historical reasons. 这种局面部分是由历史原因造成的 =Historical reasons partly lead to this situation.部分的历史原因导致了这种局面

Don't try to learn by understanding it's counterparts in English. Instead learn the root meaning of the character itself. 一定要學「部首」、「字源」，才能更了解一個漢字的意義。 由 indicates a path leading out of a field （田), thus the root meaning of this word is "origin" （e.g. "由來") if you learn this first, the usges in modern chinese will be simple to remember, since you understand their origin. (no pun intended) as a chinese person said above, "you have to understand it gradually by widely reading,learning." -- what I mentioned in this response is the shortcut, AKA correct way to learn :).

7. The nation is comprised of thirteen states. 这个国家由13个州组成。 (I believe it means "by" or "from" here. Are there other words that can be used instead like "被“ or 有？ Again, since it says"由（13个州）组成”。You should say "由“rather than "有”。if you want to use 有 in this sentence. You could say" The nation has thirteen states." 8. Before we start playing we have to decide who will be in charge of the bank. 玩儿之前我们得决定由谁来管理这些赌本。 （Means, "by" or "to leave it to somebody") Could we use "给“ or ”让“ instead? It means " leave it to someone". We usually use "给“ to express initiative. For instance, 爸爸给我买了一个书包。（My dad bought a bag for me). 9. She asked for three days off on medical grounds. 她以看病为由请了三天假。 1.(以＝in order to??? ) 2. ( 为= don't understand the use and position here) 3. (由 = reason?) Here , 由 means” excuse“ or "reason"， “以 ” means "based on..." 。 Actually， it another function of “由”， ”以。。。为由“ , in this case , it means "because ". (因为...） 10 The next radio program will be introduced by Larry. 下一个广播节目由拉里来播报。(Means, "by" or "from"? or does it mean "leave it to (somebody) to do a task"?) It could mean "by" and "leave it to someone to do a task". But do not use "from". 11. It's clear that this photo has been shot by a master. 很明显这张照片是由行家拍摄的。(Means, "by" or "from"? ) Yes, you are right. 12. This situation is partly due to historical reasons. 这种局面部分是由历史原因造成的。(Means, "because of" or "due to" can other characters be used instead like "为了“？） It means “because of, “ due to”. Again, it comes from this phrase”由。。。造成”. （because of …）.No， you cannot use 为了。 “为了”means “for something”, “for purpose of …”