在这个单元里，我们将谈论人过去的性格、外貌特点及喜好等，借此学习used to这一特有的，用来表述过去经历和习惯的语言结构。在本课的学习中，我们将一起走入哈利波特这部电影的戏里戏外，看一看经过14年，哈利波特和他的朋友们都长成什么样了？并且讨论一下哈利波特在成长过程中性格发生了哪些变化。

A Single DNA Difference in the HERC2 Gene Explains Blue Eyes 

‍A new study published in Human Genetics by Eiberget. al. shows that a DNA change in the HERC2 gene causes blue eyes. Two other studies, a study by Kaser et. al. and a study by Sturm et. al. used different approaches to find the same thing. HERC2 is a surprise since it doesn't seem tobe involved in eye color.

But the nearby OCA2 gene is. The researchers think that the DNA difference in HERC2 results in the shutting off of the OCA2 gene.And that a non-working OCA2 gene is one of the steps needed for blue eyes.

This is different than the results published last February that pointed to three DNA differences in the OCA2 gene itself that led to blue eyes. However, these three differences are very near the new difference and only explained about 2/3 of the cases of blue eyes. Most likely these differences are linked to blue eyes but don't cause them.

The researchers also found that all the blue-eyed people they looked at had the exact same DNA difference. This suggests that all of these folks came from the same blue-eyed ancestor. More analysis suggested that this blue-eyed ancestor migrated to Europe 6000-10,000 years ago where the gene spread like wildfire.

Close only Counts in Horseshoes, Hand Grenades, and Blue Eyes

Eye color happens because of the amount of the pigment melanin found in the front part of the iris. Little or no melanin there gives blue eyes. Lots of melanin in the iris gives brown eyes.

Within the last few years, scientists have identified the OCA2 gene as a major player in determining eye color. OCA2 is akey gene that's involved in determining how much melanin is made.

Some versions of OCA2 cause lots of pigment to be made and lead to brown eyes. Other versions that cause little or no pigment to get made lead to eye colors other than brown*. These other versions don't necessarily give blue eyes, though, because there are other eye color genes besides OCA2.

So how would a single mutation in a gene account for eye color? Well, there are lots of ways that this could happen. For instance, since OCA2 controls pigmentation, if it were broken, cells wouldn't have pigment. This is actually what happens in some types of albinism.

But most people with blue eyes do not have albinism. They just lack pigment in the eyes. To understand how a gene could work in one place but not in another, we need to go into a little more detail about genes.

在上一个课时的学习中，我们已经导入了used to这一语言结构，并模拟了生活的情景，展开了初步的对话操练。在这个课时中，我们将会通过阅读了解一位性格腼腆的亚裔女孩转变为流行歌手的故事，在拓展语言知识，发展技能及阅读策略的同时，体会关爱自我发展和自我完善的重要性。

Role model

A role model is a person whose behavior, example, or success is or can be emulated by others, especially by younger people. The term "role model" is credited to sociologist Robert K. Merton, who coined the phrase during his career. Merton hypothesized that individuals compare themselves with reference groups of people who occupy the social role to which the individual aspires. An example being the way young fans will idolize and imitate professional athletes or entertainmentartists.

In the second half of the twentieth century, U.S. advocates for workplace equity popularized the term and concept of rolemodels as part of a larger social capital lexicon—which also includes terms such as glass ceiling, networking, mentoring, and gatekeeper—serving to identify and address the problems barringnon-dominant groups from professional success. Mainstream business literature subsequently adopted the terms and concepts, promoting them as pathways to success for all career climbers. In 1970 these terms were not in the general American vocabulary; by the mid-1990s they had become part of everyday speech. Although the term "role model" has been criticized more recently as "outdated", the term and its associated responsibility remains prominent in the public consciousness as a commonly used phrase, and a "powerful presence" in the entertainment industry andmedia.

在现实生活中，人们有时会因为长久不见而突然发现彼此均变化不小，从而，引发今昔变化的交谈，这时，大家要么从昔日着眼，以怀旧的方式谈论过去的自己及对方，或者从今日的变化入手，谈论现实的彼此所取得的成绩。今天我们就来谈一谈这个话题所相关的语言。

与外国人交往谈话礼仪礼节

1．社交场合谈话时要弄清对方身份，以便自己谈话得体，有针对性。

2. 对外接触谈话要自然、和蔼。与外宾谈话时，应面对外宾而不是面对翻译。对方发言时要注意倾听，不要左顾右盼，频繁看表。

3．说话时不可用过大过多的手势。谈话声音不要过高，以使对方能听清为宜。

4．不要谈疾病等不愉快的事情，一般不要询问对方履历，谈及时，要十分客气，如对方不讲，不要追问。不要询问女士年龄，是否已婚等。

5．对外谈话要实事求是，自己不知道的事不要随便答复，无把握之事不要允诺，应言而有信。

6．三人以上在场，不要只谈两人知道的事，冷落其他人。

7．不要议论第三者的事情，不要交头接耳，讥笑他人，如所谈事情不便让旁人知道，则应寻找适当的时机再说。

8．谈话时不要总自己讲，应让别人也有说话的机会。别人讲话，不要随便插嘴，打断别人话头。

9．对方讲话如未听清楚，可以再问一遍。发现对方对自己讲话有误解，应进一步解释。

10．社交场合，应按本人身份，主动交际。但如别人在个别谈话，不要凑前旁听。若有事需与某人谈话，应待别人谈完。如有急事找，应先打招呼，表示歉意。