欧美日韩黄网欧美日韩日B片|二区无码视频网站|欧美AAAA小视频|久久99爱视频播放|日本久久成人免费视频|性交黄色毛片特黄色性交毛片|91久久伊人日韩插穴|国产三级A片电影网站|亚州无码成人激情视频|国产又黄又粗又猛又爽的

7．按同樣的方法，找出其余4個基準(zhǔn)點(diǎn)的4組等電勢點(diǎn)．

6．按步驟5的方法在這個基準(zhǔn)點(diǎn)兩側(cè)逐步由近及遠(yuǎn)地各探測得到5個等電勢點(diǎn)．

5．接通電源，將一探針跟AB連線上某一基準(zhǔn)點(diǎn)相接觸，然后在導(dǎo)電紙平面AB連線旁距此基準(zhǔn)點(diǎn)約lcm處輕輕移動探針，直到使電流表指針不再發(fā)生偏轉(zhuǎn)．用探針把這一點(diǎn)位置復(fù)印在白紙上．

4．在導(dǎo)電紙上畫兩個電極的連線AB，在連線上取大致相等的5個點(diǎn)作基準(zhǔn)點(diǎn)，并用探針把它們的位置復(fù)印在白紙上．

3．將兩根探針分別接到電流表的“+”、“一”接線柱上（如圖1-1所示）．

2．在導(dǎo)電紙上相距8―l0cm，平放兩個圓柱形電極（或用兩枚圖釘代替），并將電極分別與6V直流電源的正負(fù)極相連接．

1．在平整的木板上，由下而上依次鋪放白紙、復(fù)寫紙、導(dǎo)電紙各一張，導(dǎo)電紙應(yīng)將導(dǎo)電面朝上，用圖釘把三層紙一起固定在木板上．

學(xué)生用低壓電源或電池組、靈敏電流計、開關(guān)、導(dǎo)電紙、白紙、復(fù)寫紙、圓柱形金屬電極兩個、探針兩支、圖釘、導(dǎo)線若干、木板和塑料底板．

實(shí)驗(yàn)步驟

答案

œ【書面表達(dá)練習(xí)1】

Dear Mrs Brown,

We are so glad that you're coming to join us on Saturday. Here is how you can find us. We'll have our gathering party in the Central Park. Maybe you've been there, haven't you?

Go straight on when you get out of the school gate and come to the street. Then turn right at the second crossing and you'll find a hospital. Just opposite it is a No. 7 bus stop. Take a bus and get off at the fourth stop. Central Park is just in front of it. We'll have our gathering party in a boat on the lake. What a funny thing! Do come on time. We'll wait for you at the park gate.

                                                                              Yours,

                                                                           Li Hong

œ【書面表達(dá)練習(xí)2】

April 9^th, 2003

Dear Jim,

Our friend Li Ming will leave for Shanghai to study. So we are going to have a get-together at 3:30 this Friday afternoon. He lives at No.225 Dongfeng Street. It is not very difficult to find your way to his home. Take a No.2 bus, the stop of which is on the left of your university, and get off at the second crossing. There is a cinema across the street. Turn right at the corner, and you will find Dongfeng Street. Li Ming’s home is 200 yards down the street on the right. There is a post office opposite to Li Ming’s home.

                                Yours,

                                Zhang Hua

這是一篇圖畫說明文，根據(jù)圖畫，指明路線，如何到達(dá)中心公園。注意觀察圖畫，確定出發(fā)點(diǎn)、行走路線、目的地，靈活使用表達(dá)路線的表達(dá)語。

Dear Mrs Brown,

We are so glad that you're coming to join us on Saturday. Here is how you can find us. ___________________________________________________

______________________________________________________________________________________________________________________________________________________________________________________________________

Yours, Li Hong

œ【書面表達(dá)練習(xí)2】

假定你叫張華，你的同學(xué)李明即將去上海學(xué)習(xí)�，F(xiàn)由你寫一封便函給你們的朋友Jim，約他聚會。內(nèi)容要點(diǎn)如下：

（1）聚會時間：本星期五下午3點(diǎn)30分；

（2）聚會地點(diǎn)：東風(fēng)路225號，李明家。

（3）按下圖所畫路線告訴Jim怎樣去李明家。

注意：

（1）便函用英語寫，并注明便函的時間：2003年4月9日；

（2）內(nèi)容包括說明部分和要點(diǎn)；

（3）字?jǐn)?shù)：80－120。