托福聽力講座中開頭和結(jié)尾部分往往是許多題目的出題點(diǎn)所在，因此大家如果能夠在聽的過(guò)程中把握好這兩個(gè)部分，今天小編給大家?guī)?lái)了托福聽力講座開頭結(jié)尾常見信號(hào)詞匯總一覽，希望能夠幫助到大家，下面小編就和大家分享，來(lái)欣賞一下吧。

托福聽力講座開頭結(jié)尾常見信號(hào)詞匯總一覽

托福聽力講座開頭部分信號(hào)詞一覽

說(shuō)話者表達(dá)主旨或談話的目的的語(yǔ)句往往出現(xiàn)在開頭的幾句話，是把握全局的重點(diǎn)。

信號(hào)詞：(專家建議考生，每天要把所有的信號(hào)詞讀個(gè)幾遍，強(qiáng)迫自己聽到這個(gè)詞馬上反應(yīng)過(guò)來(lái)這里有考點(diǎn))

Today, we’ll focus on/constrated/discuss…

Today, our topic is…

Let’s…

特殊情況(也經(jīng)常出現(xiàn))：開頭會(huì)將講一些上次課講的東西，作為復(fù)習(xí)，之后才是主旨，我們把這種情況稱為：Miss start

注意：出現(xiàn)Miss Start，上次課講的東西一定要聽，在這部分很可能出細(xì)節(jié)題

Miss Start 信號(hào)詞：Before we get started, let’s review what we’ve learned last class…

Let’s pick up where we left off last week, OK, as you recall(記得)…

Before we begin our discussion on…(此處為本次主題)，Let’s review what we know about…(此處為上次主題)

間接開頭： In your text book, the author says that… (主題出現(xiàn))，I thought we all to/should take sometime to talk about it. (不一定完全一樣，但是類型差不多)

托福聽力講座結(jié)尾部分信號(hào)詞匯總

托福聽力的結(jié)尾部分往往出現(xiàn)一些總結(jié)性信息以及其他一些涉及考點(diǎn)的內(nèi)容，應(yīng)充分重視。

信號(hào)詞：

To some up

To conclude/in conclusion

In summary/to summarize

Finally

Therefore

From this, we can see that…

2020托福聽力練習(xí)：蜜蜂通過(guò)味道給花粉排名

Walk through Times Square—you're bombarded with advertising. And it turns out, a bumblebee might have a similar feeling, buzzing through a field of flowers. "So these flowers are these billboards, they're advertising a good, this delicious nectar reward, and bees are very picky shoppers." Anne Leonard, a pollination biologist at the University of Nevada, Reno.

She describes a flower field as a sort of pollination marketplace. And one way bees choose where to visit? "Bees are nectar experts. They are really good at assessing even really small differences in the sugar concentration of nectar." They also scope out the shape and size of the flowers, and their color and scent. And now Leonard and her colleagues have discovered that bumblebees are pollen aficionados, too.

They found that out by lacing batches of cherry pollen with either table sugar or bitter quinine. And to display the pollen to bees, "We got really into it—we started 3-D printing flowers in our lab." And for the anther—the male flower part, which presents the pollen—pipe cleaners. "So we bought out Michael's craft store supplies of these pipe cleaners and used them in our experiments."

Turns out bees would return again and again to the same color flower that dispensed sweet pollen, and spend more time collecting there. But when confronted with the bitter pollen? They sought a different colored flower for their very next stop. All of which suggests that, in addition to savoring nectar, bees taste pollen too—and judge flowers by it. The results are in the journal Biology Letters.

The finding means that plants have to find a happy medium: "So can you make your pollen attractive enough that the bees will collect it, but distasteful enough that they won't collect too much of it?" And that balancing act, of carefully calibrated chemistry—it's just one of the many transactions that plays out in the buzzing pollination marketplace. Where the object is to make a sweet profit.

走過(guò)紐約時(shí)代廣場(chǎng)，你會(huì)被廣告不斷侵?jǐn)_。事實(shí)證明，熊蜂在嗡嗡地飛過(guò)花田時(shí)，可能會(huì)有類似的感覺?！耙?yàn)檫@些花朵就像是那些廣告牌，它們?cè)跒檫@些美味可口的花蜜打廣告，而蜜蜂就是那些非常挑剔的消費(fèi)者?！眱?nèi)華達(dá)州立大學(xué)雷諾分校的傳粉生物學(xué)家安妮·倫納德說(shuō)道。

她將花田描述為一個(gè)授粉市場(chǎng)。蜜蜂選擇去哪里采集花蜜的方法是什么?“蜜蜂是花蜜專家。它們很擅長(zhǎng)評(píng)估花蜜，即使花蜜糖的濃度存在微小的區(qū)別它們也能感覺到。”它們還能確定花的形狀、大小、顏色和氣味。現(xiàn)在倫納德和她的研究團(tuán)隊(duì)發(fā)現(xiàn)，熊蜂也是花粉愛好者。

他們通過(guò)給不同批次分別含有甜蔗糖和苦奎寧的櫻桃花粉系上標(biāo)簽的方法進(jìn)行研究，并得到了上述結(jié)論。為了向蜜蜂展示花粉，“我們進(jìn)行了非常深入地研究，我們開始在實(shí)驗(yàn)室用3D技術(shù)打印花朵?！痹诨ㄋ幉糠郑簿褪浅尸F(xiàn)出花粉的雄花部分使用清管器?！八晕覀冑?gòu)買了邁克爾工藝品店的清管器，將這些清管器應(yīng)用到我們的實(shí)驗(yàn)中?！?/p>

實(shí)驗(yàn)證明，蜜蜂會(huì)在含有甜蔗糖花粉的相同顏色花朵間重復(fù)往返，并且花費(fèi)更多的時(shí)間來(lái)采集。那它們遇到含有苦奎寧的花粉時(shí)會(huì)怎樣呢?它們會(huì)在下一次停留時(shí)尋找一種與之顏色不同的花朵。所有這一切表明，除了品嘗花蜜，蜜蜂也會(huì)品嘗花粉的味道，并且通過(guò)花粉來(lái)對(duì)花朵進(jìn)行評(píng)估。該研究結(jié)果刊登在《生物學(xué)快報(bào)》雜志上。

該研究結(jié)果表明，植物必須找到一個(gè)折中的辦法：“你能讓你的花粉有足夠的吸引力，讓蜜蜂來(lái)采集，但是又讓花粉不太合口，確保蜜蜂不會(huì)采集太多嗎?”這一精確校準(zhǔn)化學(xué)的平衡做法，只是蜜蜂授粉市場(chǎng)上進(jìn)行的眾多交易中的其中一種。該市場(chǎng)的目標(biāo)是獲得“甜蜜”的利潤(rùn)。

重點(diǎn)講解：

1. be good at 擅長(zhǎng)的;精通的;能干的;

例句：The conductor is good at keeping the players together.

樂隊(duì)指揮善于使表演者奏協(xié)調(diào)。

2. buy out 買下…的股權(quán)(或產(chǎn)權(quán));

例句：The bank had to pay to buy out most of the 200 former partners.

銀行不得不花錢買下過(guò)去200名合伙人手中的大部分股權(quán)。

3. be confronted with (問(wèn)題、任務(wù)或困難)降臨，使面臨;

例句：There is always turmoil when humans are confronted with change.

當(dāng)人類面對(duì)改變的時(shí)候，總是有混亂。

4. in addition to 另外;加之;除…之外;

例句：In addition to the radio, newspapers were also a main source for information.

除了無(wú)線電廣播外，報(bào)紙也是一種主要信息來(lái)源。

5. play out (使)(戲劇性的事件)逐漸發(fā)生;(使)展開;

例句：We play out an imaginary confrontation in our mind.

我們的腦海中浮現(xiàn)出一種想象的沖突。

2020托福聽力練習(xí)：海豚通過(guò)鼻涕粘液發(fā)聲

Sometimes a snout full of snot can be just what the doctor ordered. At least if you're a dolphin. Because a new study shows that a little bit of mucus helps these marine mammals generate the rapid-fire stream of clicks they emit and use for echolocation.

First off, let's just get this out of the way. Dolphins do not actually sound like this. [Flipper laugh sound] That's a made-for-TV giggle that some say is actually the doctored call of a bird: the Australian kookaburra.

Real dolphins, like these bottlenoses, sound more like this. [Bottlenose sounds] They use their clicks, chirps and whistles to navigate, communicate and to catch their next meal. The high-frequency clicks, in particular, help Flipper and his kind locate and track fish dinners.

Dolphins make these sounds by forcing air through a nasal passage just beneath the blowhole. In this nasal region are liplike flaps of tissue called dorsal bursae that vibrate and collide to produce dolphin talk.

Now, a team of researchers has created a simplified model that can reproduce this characteristic dolphin chatter. And they found that the secret ingredient is snot.

While looking through the literature, oceanographer Aaron Thode stumbled across a model that represented vocal cords as masses connected by springs—which store and release energy—and dampers, which dissipate that energy. This model successfully replicated the essential characteristics of the system, like the frequency of vocal cord vibration.

So Thode enlisted his father Lester, a retired nuclear physicist from Los Alamos National Lab, to help him fit the model to a dolphin's nasal anatomy. When the Thodes compared the simulated sounds produced by their model to a recording of actual dolphins, they found that the model mimicked both the loud thump and extended ring that are part of the natural click. That's the sound, but slowed down to make it audible to our ears.

The initial thud comes from when those dorsal bursae collide. And the reverberation results from the vibrations that linger when the tissues pull apart. But Thode the younger says the bursae have to be somewhat sticky for the clapping together and snapping apart to produce a noise with the correct loudness and pitch. That stickiness comes courtesy of the mucus. Thode vocalized the results at the meeting of the Acoustical Society in Salt Lake City.

The match between the simulated sounds and the real deal is encouraging, and the Thodes plan to keep up their collaboration to refine their model. "Yeah, I guess some fathers and sons bond over football, but my dad and I, I guess we bonded over differential equations and writing this paper."

如果你是一只海豚，醫(yī)生會(huì)要求你鼻子里充滿鼻涕。因?yàn)橐豁?xiàng)新研究表明，一點(diǎn)粘液有助于這些海洋哺乳動(dòng)物發(fā)出急速連續(xù)的咔噠聲并利用回聲進(jìn)行定位。

首先，我們要說(shuō)明一下。海豚實(shí)際上并不會(huì)發(fā)出這樣的聲音。(海豚飛寶的笑聲)這種咯咯的笑聲出自一部電視電影，有人說(shuō)那實(shí)際上是用澳大利亞笑翠鳥的叫聲偽造的。

真正的海豚，像這些寬吻海豚，它們的聲音聽起來(lái)更像這樣。(寬吻海豚的聲音)它們通過(guò)發(fā)出的咔噠聲、啾啾聲和口哨聲來(lái)進(jìn)行導(dǎo)航、交流和捕食。尤其高頻咔噠聲可以幫助海豚飛寶和它的同類進(jìn)行定位，追蹤用作晚餐的魚類。

海豚迫使空氣穿過(guò)氣孔之下的鼻道制造出聲音。海豚的鼻區(qū)有被稱為背側(cè)黏液囊的唇形片狀瓣膜，通過(guò)振動(dòng)和碰撞讓海豚能夠“講話”。

現(xiàn)在，一個(gè)研究小組建立了一個(gè)可重現(xiàn)海豚叫聲特征的簡(jiǎn)化模型。他們發(fā)現(xiàn)，秘密成分是鼻涕。

在瀏覽文獻(xiàn)時(shí)，海洋學(xué)家亞倫·索德偶然發(fā)現(xiàn)了一個(gè)模型，這個(gè)模型將聲帶描繪成由彈簧相連、可以儲(chǔ)藏和釋放能量的集塊，以及消散能量的阻尼器。這一模型成功地復(fù)制了發(fā)聲系統(tǒng)的基本特征，如聲帶振動(dòng)的頻率。

索德的父親是美國(guó)洛斯阿拉莫斯國(guó)家實(shí)驗(yàn)室的退休核物理學(xué)家，索德邀請(qǐng)他的父親萊斯特加入研究，幫助他使這個(gè)模型與海豚的鼻部解剖構(gòu)造相符合。當(dāng)他們將模型產(chǎn)生的模擬聲音與海豚真實(shí)聲音的錄音進(jìn)行比較時(shí)，他們發(fā)現(xiàn)，這個(gè)模型模擬的撞擊聲和延長(zhǎng)形成的環(huán)狀結(jié)構(gòu)就是海豚發(fā)出的咔噠聲的一部分。這就是模型發(fā)出的聲音，不過(guò)我們放慢了速度讓大家可以聽清。

最初的撞擊聲來(lái)自背側(cè)黏液囊的碰撞。而回聲則來(lái)源于組織分離時(shí)產(chǎn)生的振動(dòng)。不過(guò)小索德認(rèn)為，黏液囊必須要有足夠的粘性，一下靠攏又分開，才能產(chǎn)生這種聲音并達(dá)到正確的音量和音高。這種粘性來(lái)自粘液。索德在鹽湖城舉行的聲學(xué)學(xué)會(huì)上發(fā)表了這一研究成果。

模擬聲音與海豚原聲的匹配度令人鼓舞，索德父子計(jì)劃繼續(xù)合作下去，完善他們的模型?！拔艺J(rèn)為有些父子因足球而親密，而我爸爸和我是因?yàn)槲⒎址匠毯妥珜戇@篇論文而親密起來(lái)的?！?/p>

重點(diǎn)講解：

1. in particular 尤其;特別;

例句：She stressed that point in particular.

她特別強(qiáng)調(diào)了那一點(diǎn)。

2. stumble across 意外發(fā)現(xiàn);偶然看見;

例句：I stumbled across an extremely simple but very exact method for understanding where my money went.

我意外發(fā)現(xiàn)了一個(gè)非常簡(jiǎn)單卻能精確了解我所花錢去向的方法。

3. part of 一些;部分;

例句：The astronaut accepted danger was part of the job.

太空人承認(rèn)他們的工作中包含著危險(xiǎn)。

4. keep up 繼續(xù)做(或提供);

例句：You can't keep up the pretense any longer.

你無(wú)法繼續(xù)偽裝下去了。