At large?在逃的，未被捕獲的

????Pumas are large, cat-like animals which are found in America.?

Be found in?習(xí)語(yǔ)，產(chǎn)于，存在于,所以用的一般現(xiàn)在時(shí) Which are?可以省略，關(guān)系代詞做主語(yǔ)謂語(yǔ)動(dòng)詞是be

When reports came into London Zoo that a wild puma had been spotted forty-five miles south of London, they were not taken seriously.?

在when時(shí)間狀語(yǔ)從句中Reports?主語(yǔ)?came謂語(yǔ)?into London zoo賓語(yǔ) ?That?是report?同位語(yǔ)從句為了句式平衡就隔開了 take ... seriously認(rèn)真對(duì)待…… Spot?動(dòng)詞表示發(fā)現(xiàn)

However, as the evidence began to accumulate, experts from the Zoo felt obliged to investigate, for the descriptions given by people who claimed to have seen the puma were extraordinarily similar.

feel obliged to do sth:覺得有義務(wù)/應(yīng)該/不得不做某事。 felt是系動(dòng)詞，而obliged是形容詞。這句話是系表結(jié)構(gòu) given by people作定語(yǔ)，修飾descriptions，相當(dāng)于descriptions which were given by people，用這種分詞結(jié)構(gòu)的好處是：分詞結(jié)構(gòu)跟在名詞后面，銜接更加緊湊

The hunt for the puma began in a small village where a woman picking blackberries saw 'a large cat' only five yards away from her.?

Picking?非謂語(yǔ)主動(dòng)，當(dāng)后置定語(yǔ)修飾women?

It immediately ran away when she saw it, and experts confirmed that a puma will not attack a human being unless it is cornered.?

賓語(yǔ)從句中的will不是用來(lái)表示將來(lái)時(shí)的助動(dòng)詞，而是用來(lái)表示習(xí)慣性或動(dòng)作特征的情態(tài)助動(dòng)詞，表示“就，就會(huì)，總是”之意，例： Mary will read for hours.?瑪麗常常一連讀書幾小時(shí)。 human being是一個(gè)詞組，意思是“人”

The search proved difficult, for the puma was often observed at one place in the morning and at another place twenty miles away in the evening.?

https://baike.baidu.com/item/系動(dòng)詞/3638954?fromtitle=聯(lián)系動(dòng)詞&fromid=387904&fr=aladdin prove (to be)+adj/n?被證明是……/聯(lián)系動(dòng)詞直接跟表語(yǔ) -His injury proved (to be)fatal

-The operation proved (to be) a success

Wherever it went, it left behind it a trail of dead deer and small animals like rabbits.?

leave sth. behind把…留在身后；忘帶；在…之后造成。 此處由于賓語(yǔ)a trail of dead deer and small animals like rabbits較長(zhǎng)，如果直接將其放在謂語(yǔ)left之后，則會(huì)顯得頭重腳輕，因此此處將狀語(yǔ)behind it放在句子中間，以平衡首尾。 a trail of:?一連串的

Paw prints were seen in a number of places and puma fur was found clinging to bushes.?

現(xiàn)在分詞短語(yǔ)clinging to bushes用作puma fur的主語(yǔ)補(bǔ)足語(yǔ)。

Several people complained of 'cat-like noises' at night and a businessman on a fishing trip saw the puma up a tree.?

on a fishing trip：去釣魚?那么同樣的，去出差或是公干也能說(shuō)成是“on a business trip”。

The experts were now fully convinced that the animal was a puma, but where had it come from ??

Be convinced that?使某人相信，被動(dòng)語(yǔ)態(tài)

As no pumas had been reported missing from any zoo in the country, this one must have been in the possession of a private collector and somehow managed to escape

had been reported”?根據(jù)上下文語(yǔ)境來(lái)看發(fā)生在

?

第二句中“

The experts were now fully convinced

”之前，所以用過(guò)去完成時(shí)態(tài)。 in the possession of sb.?被某人占有；屬于…；為…所有。例： The keys are in the possession of the caretaker.?那些鑰匙由管理員持有。 Missing?形容詞，丟失的

The hunt went on for several weeks, but the puma was not caught. It is disturbing to think that a dangerous wild animal is still at large in the quiet countryside