Unit 1 Happy birthday.教学设计

1．教学目标

知识目标：

（1）学生能掌握本课新单词: happy, birthday, here(here’s=here is), present, this, pencil, pen, cake.

（2）学生能运用Happy birthday! 及Here’s...祝福他人生日快乐并赠送礼物。 技能目标：学生能运用Happy birthday!表达生日祝福，用Here’s...赠送礼物。 情感目标：

（1）学生了解西方生日文化中赠送与接收礼物的礼节与习惯；

（2）向同学表达生日祝福，以此培养和增进友谊。

（3）通过小组合作学习培养学生的自主，合作，探究意识。

2．学情分析

大多数三年级上学期的孩子第一次正式接触英语，这个年龄段的孩子好奇心强，喜欢表演和游戏，擅长模仿，我发现，很多的孩子是喜好英语并希望能学好英语的，所以在一先开始的几堂英语课中，他们表现的也都很积极、认真。学生学英语不久，有可能说的不好，有的还不敢说，课堂上要以表扬为主，注重培养学习英语的兴趣，学生喜欢直观形象思维，对游戏、竞赛特别感兴趣。鼓励他们大胆说、积极做、努力唱。有着极强的求知欲强和表现欲。根据学生的心理特点我课上多以表扬为主，注重对学生英语学习兴趣的培养，鼓励他们大胆说、积极做、努力唱。在教学中若能创设情境给孩子学习和操练新知，并通过自然拼读法教授新单词，那么孩子的学习就不会那么生硬和被动，要让孩子主动快乐地投入到英语学习中。

3．重点难点

教学重点:

掌握本课新单词；运用Happy birthday! 及Here’s...祝福他人生日快乐并赠送礼物。 教学难点：Present的读音；运用Here’s...赠送礼物。

4．主要教学方法及教学策略分析:

根据对教材的分析,教师采用多媒体辅助教学，同时采用情景教学法、直观演示法、游戏教学法、调查法等教学方法，并坚持以任务型活动来安排本单元教学。由歌曲开始，创设语言氛围，通过情景对话，游戏、韵律、自编歌曲等教学环节，激发学生的学习兴趣，充分发挥学生的主体作用，突破难点，使学生在参与活动的过程中发展学生的综合语言运用能力。

5．教学辅助：

单词卡、实物（包裹好的钢笔、铅笔、书等） 、多媒体课件

6．教学过程

Step 1 Greetings and Sing the song “Good morning, Sam”.

T: Are you happy today? Ss: Yes! (利用单词卡教授happy)

T: Look! The three boys are happy, too.（课件展示）They are brothers. Why are they happy? Because today is their birthday. Do you know birthday? (利用单词卡教授birthday) 播放动画. Amy is their good friend. Let’s see what does Amy say to the three boys. Who are they? They are Jim, Tim and Kim.

T: What does Amy say to them?

Ss: Happy birthday. (利用句子磁条 Happy birthday）

T：请同学们听课文录音，模仿语音语调跟读。

T: Now, boys and girls. 让我们分别给他们送上生日的祝福，好吗？

Ss: Happy birthday, Jim./ Tim./ Kim.

T: Can you sing the song“Happy birthday”?

(Sing a song“Happy birthday!”and lead in Module 6 Unit 1 Happy birthday!

(全班齐唱生日歌，教师分发糖果礼物给三位同学，说Here’s your present） T：今天还是我们一位老朋友的生日，Who is he? Let’s look!

Step 2 Presentaion

播放动画，(板书课文标题）观看完后，T：Whose birthday? Ss: Sam.（头饰展示） T: Yes! Today is Sam’s birthday. We should say...

Ss: Happy birthday, Sam! T: Thank you.

T：Who is it?(头饰展示）

Ss: Daming. T: Sam的好朋友Daming来给Sam送礼物了。他是怎么送出他的礼物的呢？Sam又是怎样表示感谢的呢？Now，Let’s listen. Please open your books and turn to page 32. Look at activity

2. Listen and point.(播放课文视频）T：What does Daming say? S: Here’s your present. T：当我们给别人送礼物的时候，We can say: Here’s your present.

（板书）利用磁条教授Here’s .

T: Look. Here’s means here is.

T: Oh, What’s this? (展示道具礼物盒），It’s a present.利用单词卡教授present.

由于present这个单词发音较难，所以采用男女生读，大小声读，分组读等方法进行教学。拿出两个“present”的盒子，猜一猜盒子里面装的是什么东西？然后老师拆开盒子，引入单词“pen”和“pencil”。在把它们送给过生日的学生，复习句型“Here’s your pen/pencil。让学生进行练习。

T: Sam收到礼物时是怎样表示感谢的呢？Ss: Thank you. (板书）T：Oh，I’m Daming. You

are Sam. OK? Happy birthday, Sam. Here’s your present.

Ss: Thank you, Daming. Let’s change...

师生互换，男生女生互换角色扮演Sam和Daming操练重点句型。

T：I’m Daming again. You are Sam（随机抽点一名男生与教师对话）..

.出示道具礼物盒，T：What’s this?

打开看一看，在西方国家小朋友收到礼物的时候，都会当面打开，告诉大家他收到的是什么礼物。利用单词卡片及实物教授pen和pencil，念韵句pen and pencil, pencil and pen. T: How about Ms Smart? Ms Smart给Sam送了什么生日礼物呢？

Let’s listen. (播放相关课文视频） 教授cake.教师拿出蛋糕,

T: How many candles? Let’s count. Ss: One, two?nine!

T: So Sam says“I’m nine”. Now，please listen again and read after the reading pen. (播放课文视频，学生跟读）。

Step3 consolitaion

1. 全组齐读课文。

2. 分角色朗读课文。

3. 1人扮演Sam，1人扮演Daming, 1人扮演Ms Smart.）

4. 学习小组成员向即将过生日的成员分别送上生日祝福及礼物。（老师可以提供道具作

为礼物，也可以是学生使用自己的文具等作为礼物。）

Step4 Exercises

一、看单词选择正确的图片：

（ ) 1. pen ( ) 2. present ( ) 3. pencil ( ) 4. cake

二、情景反应，选择正确的答案：

( ) 1. 你的朋友过生日，你应该怎么说呢？

A. How are you? B. Happy birthday!

( ) 2. 当你送礼物给你的朋友的时候，你应该说：

A. Here’s your present. B. Thank you!

( ) 3. 当你收到别人的礼物的时候，你应该说：

A. Hello！ B. Thank you!

Step5 Homework:

1.读Module6 Unit1 课文三遍。

2.制作一张生日卡片。

第二篇：S5.4 secondary circulation and spin down 次级环流和旋转减弱 presentation演讲稿

Good evening everyone. My topic is section five point four, secondary circulation and spin down. [click]

There are five parts in my presentation, key words, secondary circulation, spin down, Physical meaning,and summary.

[click]Firstly, let us see the key words. The secondary circulation is a circulation superposed on the primary circulation by the physical constraints of the system. And the spin down is a mechanism for destroying vorticity in a rotating atmosphere by losing angular momentum. The Angular momentum measures an object's tendency to continue to spin. And angular momentum is equal to the vector product among mass, velocity and distance (from point object is spinning or orbiting around)[click] Both the mixed-layer solution and the Ekman spiral solution indicate that in the planetary boundary layer the horizontal wind has a component directed toward lower pressure. As the rad arrows shown in Fig. 5.6, [click]this implies mass convergence in a cyclonic circulation and mass divergence in an anticyclonic circulation, which by mass continuity requires vertical motion out of and into the boundary layer, respectively. [click] In order to estimate the magnitude of this induced vertical motion, we note that if vg = 0 so that ug is independent of x, the cross isobaric mass transport per unit area at any level in the boundary layer is given by ρ0v. For the Ekman spiral, it is given by the equation five point thirty five, where De is equal to πdivide byγ, and is the Ekman layer depth defined in Section 5.3.4.[click]Integrating the mean continuity equation (5.13) through the depth of the boundary layer gives equation five point thirty six. Assuming that w(0) = 0, and vg = 0 , and comparing with (5.35) that the mass transport at the top of the Ekman layer is given by equation five point thirty

seven.

[click]Noting that minus partial ug divide by partial y is just the geostrophic vorticity in this case. we find equation five point thirty eight after substituting into (5.36), where we have neglected the variation of density with height in the boundary layer and have assumed that one plus e to minus π is approximately equal to 1. Hence, we obtain the important result that the vertical velocity at the top of the boundary layer is proportional to the geostrophic vorticity. In this way the effect of boundary layer fluxes is communicated directly to the free atmosphere through a forced secondary circulation. This process is often referred to as boundary layer pumping. It only occurs in rotating fluids and is one of the fundamental distinctions between rotating and nonrotating flow. For a typical synoptic-scale system , the vertical velocity given by (5.38) is of the order of a few millimeters per second. [click]

An analogous boundary layer pumping is responsible for the decay of the circulation created when a cup of tea is stirre. Radial inflow takes place near the bottom of the cup. By continuity of mass, the radial inflow in the bottom boundary layer requires upward motion and a slow compensating outward radial flow throughout the remaining depth of the tea. This slow outward radial flow approximately conserves angular momentum, and by replacing high angular momentum fluid by low

angular momentum fluid serves to spin down the vorticity in the cup far more rapidly than could mere diffusion. [click]

For synoptic-scale motions the barotropic vorticity equation (4.24) can be written approximately as equation four point twenty four. where we have neglected ζg compared to f in the divergence term and have also neglected the latitudinal variation of f .Recalling that the geostrophic vorticity is independent of height in a barotropic atmosphere, (5.39) can be integrated easily from the top of the Ekman layer (z = De) to the tropopause (z = H) to give equation five point forty. Substituting for w(De) from (5.38), assuming that w(H) = 0 and that H is much lager than De, the equation (5.40) may be written as equation five point forty one. This equation may be integrated in time to give equation five point forty two.where ζg(0) is the value of the geostrophic vorticity at time t = 0, and τe is the time that it takes the vorticity to decrease to e ?1 of its original value. [click]

This e-folding time scale is referred to as the barotropic spin-down time. Taking typical values of the parameters as follows, we find that τe approximates 4 days. Thus, for nidlatitude synoptic-scale disturbances in a barotropic atmosphere, the spin-down time is a few days. This decay time scale should be compared to the time scale for ordinary viscous diffusion. For viscous diffusion the time scale can be estimated from scale analysis of the diffusion equation five point forty three.So that for the above value of H and Km, the diffusion time scale is thus about 100 days. Hence, in the absence of convective clouds the spin-down process is a far more effective mechanism for destroying vorticity in a rotating atmosphere than eddy diffusion. [click]

Physically the spindown process in the atmospheric case is primarily the Coriolis force that balances the pressure gradient force away from the boundary. The Coriolis force for the outward-flowing fluid is directed clockwise, and this force thus exerts a torque opposite to the direction of the circulation of the vortex. In the case of boundary layer, viscosity is responsible for the presence of the secondary circulation. In a stably stratified baroclinic atmosphere, the buoyancy force will act to suppress vertical motion. So the interior secondary circulation will decrease with altitude, shown in Fig. five point eight. This flow will rather quickly spin down the vorticity at the top of Ekman layer that is enough to bring ζg to zero. The result is a baroclinic vortex with a vertical shear of the azimuthal velocity that is very strong. [click]This vertical shear of the geostrophic wind requires a radial temperature gradient that is in fact produced during the spin-down phase by adiabatic cooling of the air forced out of the Ekman layer.[click]

Finally, let us see my summary. By the physical constraints of the system, a secondary circulation will occur. It only occurs in rotating fluids. And in boundary layer, viscosity is responsible for the presence of it. The secondary circulation can spin down an atmosphere vortex. The e-folding time is referred to as the barotropic spin-down time. The secondary circulation in the baroclinic atmosphere serves two purposes: it changes the azimuthal velocity field of the vortex through the action of the Coriolis force and it changes the temperature distribution so that a thermal wind balance is always maintained between the vertical shear of the azimuthal velocity and the radial temperature gradient. That’s all.

Thanks four your attention, thank you!