Using animals to test drugs intended for humans is controversial, with critics arguing there are other ways to ensure new medicines are safe and effective. But the scientists who carry out the research say animal studies remain necessary. Statistics indicate that in the UK around three million mice are being used for research and tens of millions worldwide.

Despite the difference in appearances, the genetic similarities with humans are     1    . The mouse genome (基因组) shares over 95% of its genes with humans. The animal acts as a “model”, genetically     2     to develop a human disease. But the use of mice, like any animal, in research is criticized by some.

Animal Defenders International (ADI) is one of the groups that campaigns for an end to the use of animals in research. “We would argue that it is extremely outdated, and not very good science for humans,” says Fleur Dawes of ADI. Ms. Dawes believes the suffering that the animals go through does not legalize their     3     to science and medicine for humans.” There is a big problem with that because there are huge differences between the species. And even though there are similarities with humans and mice, they react very differently to each other when experimented on. So what works in one animal is not an indication that that is how things work in other animals.”

However, Dr. Wells from Mary Lyon Centre (MLC) says they are constantly trying to     4     the process to reduce the suffering of mice.” If it’s a procedure where you can anaesthetize (麻醉) the mice, then you do it to reduce their stress. And if there is a (n)     5     method that doesn’t involve mice, you are not legally and normally allowed to do the procedure.”

If we     6     animal research, are there alternatives? Dr. Wells says, “There is a massive field     7     on alternatives, and we are very supportive of that field and we always keep track of what is going on in that field, because maybe we can replace one of our models. “Those alternatives include chips on human organs to study their function, micro-dosing treatments in humans and     8     models.” Lots of people say that there is a computer now to model what is going to happen in diseases,” Dr. Wells adds, “But we still don’t know enough to program those computers with     9     knowledge to be able to model what’s happening in every disease.”

Fleur Dawes agrees one alternative is not enough. But she says, “By combining the different alternatives, you can actually get a much better picture that is of much better     10     to humans.”

7 . My father decided to start learning French when he was 57. On the surface, his retirement hobby seems a little random — our family has no connection to French-speaking countries — but his ______ ran deeper than a passion for cakes. My grandmother developed signs of Alzheimer’s disease (阿尔兹海默症) in her early 70s, and studies suggest that being bilingual, that is, being able to speak two languages equally well, can ______ the start of the condition by up to five years. Drawn by that ______ benefit, many people have attempted to pick up a new language in adulthood.

Lots of activities are linked to better brain health in old age, like getting more education when you’re younger and physical activity. Experts say regularly speaking multiple languages may be especially ______ though. “We use language in all aspects of daily life, so a bilingual brain is ______ working,” said Mark Antoniou, a professor at Western Sydney University who specializes in bilingualism.

The age at which you learn another language appears to be less important than how ______ you speak it. The cognitive (认知的) benefit is from having to ______ your mother tongue, which your brain is forced to do if you’re trying to recall the right words in another language. So if the second language is used a lot, you’re getting that cognitive ______. That process is called cognitive inhibition. In theory, by improving these types of processes, the brain becomes stronger to the ______ caused by diseases like dementia. The stronger your mental power, the thinking goes, the longer you can function normally, even if your brain health starts to ______.

However, evidence for the benefits of learning a second language as a hobby in your 60s is ______. Research by Dr. Antoniou and colleagues found that while Chinese adults 60 and up improved on cognition tests after a six-month language learning program, people who played games like Sudoku did as well. Two more recent studies on the topic found virtually no ______ in cognitive performance after people took part in language-learning programs.

The scientists who conducted those studies offered a few potential ______. One is that the participants were highly motivated volunteers, who may have already been at peak performance for their age, making it hard to see any ______. Another is that the language interventions were perhaps too short. The handful of studies looking into the issue have used language lessons that were very different in their ______ and frequency. Some studies taught participants for eight months, others for just one very intense week.

8 .

9 . The way of recording things has never ceased to develop. In the 1980s, as sales of video recorders went up, old 8mm home movies were gradually replaced by VHS (video home system)tapes. Later, video tapes of family holidays lost their appeal and the use of DVDs ______. Those, too, have had their day. Even those holding their childhood memories in digital files on their laptops now know these files face the risk of ______.

Digitising historical documents brings huge benefits—files can be ______ and distributed, reducing the risk of their entire loss through physical damage caused by fire or flooding. And developing digital versions reduces ______ on the original items. The International Dunhuang Project, ______, has digitised items like manuscripts (手稿) from the Mogao caves in China, enabling scholars from around the world to access records easily without touching the real items.

But the news that the Ministry of Justice of the UK is proposing to scan the 110 million people’s wills it holds and then destroy a handful of ______ after 25 years has shocked historians. The ministry cites this as a way of providing easier access for researchers. But that only justifies digitisation, not the ______ of the paper copies. The officials note the change will be economically efficient (saving around £4.5m a year) while keeping all the essential information.

Scholars ______. Most significantly, physical records can themselves carry important information — the kind of ink or paper used may be part of the history that historians are ______. and error s are often made in scanning. Besides, digital copies are arguably more ______ than the material items, just in different ways. The attack from the Internet on the British Library last October has prevented scholars from ______ digitised materials it holds: imagine if researchers could not return to the originals. Some even think digitised information can easily be lost within decades no matter what ______ are put in place.

The government says that it will save the original wills of “famous people for historic record”, such as that of Princess Diana’s. However, assuming that we know who will ______ to future generations is extraordinarily proud. Mary Seacole, a pioneering nurse who now appears on the national school course in the UK, was largely ______ for almost a century.

The digitisation of old documents is a valuable, even essential measure. But to destroy the originals once they have been scanned, is not a matter of great ______, but of huge damage.

10 . Anyone who has ever witnessed the miracle in which infants progress from mewling to “Mama” to “Mine!” knows how critical it is for youngsters to hear normally before they speak their first words. _______, many children who don’t talk by age two turn out to be deaf. The sooner their disability is discovered and _______, the less likely they are to fall behind in the development of important language and social skills. That is why a growing number of hearing specialists (audiologists) and parents are campaigning for _______ screening of newborns for hearing loss.

Their _______ has registered in some powerful ears. To date, 22 states have passed legislation requiring at least partial screening programs. Part of the push stems from _______ in technology that, among other things, allow children as young as two months to be _______ hearing aids. But there are limits to the technology. One thing parents should realize before they start is that the screening tests are far from _______. A bad result doesn’t necessarily indicate a problem.

Audiologists estimate that 3 out of every 1,000 babies are born with some kind of hearing loss. Of those three infants, one is profoundly deaf. About half the time, doctors can identify a possible cause, such as a birth weight less than 5 pounds, or a family history of _______. The rest of the time there is simply no _______ as to why a newborn’s hearing may have been affected.

The screening tests work by introducing a sound into a baby’s ear and then measuring either the ________ of the ear’s internal mechanisms or the electrical activity of the auditory portion of the brain (the auditory brain-stem response test). Just because a baby fails either test, ________, does not mean that there is a hearing problem. A temporary buildup of fluid in the ear canal or excessive noise in the nursery can ________ the results. For this reason, experts say, hospitals should ________ the screening tests for any baby who doesn’t pass the first time before telling the parents to consult an audiologist for more thorough testing.

It is at this stage that things get a bit ________. Though 20 of every 1,000 babies fail the two-step screen, most prove on further examination to be just fine. Is it worth ________ 17 families of perfectly normal children - not to mention asking them to spend several hundred dollars on advanced tests — to identify three infants with hearing loss?