单选题 By far the most common snake in Britain is the adder(喹蛇). In Scotland, in fact, there axe no other kinds of poisonous snake. It can be found almost anywhere, but it prefers sunny hillsides and rough open country, including high ground. In Ireland there are no snakes at all.
Most people regard snake bites as deadly, but not all bites are serious, and very few are deadly. Some- times attempts at emergency treatment turn out to be mere dangerous than the bite itself, with someone heroically, but mistakenly, trying do-it-yourself surgery(外科手术)and other unnecessary measures.
All snakes have small teeth, so it follows that all snakes can bite, only the bite of the adder presents any danger. British snakes axe shy animals and are fax more frightened of you than you could possibly be of them. The adder will attack only if it feels threatened, as can happen if you take it by surprise and step on it accidentally, or if you try to catch it or pick it up, which it dislikes strongly. If it hears you coming, it will normally get out of the way as quickly as it can, but adders cannot move very rapidly and may attack before moving if you axe very close.
The effect of a bite changes considerably. It depends upon several things, one of which is the body-weight of the person bitten. The bigger the person, the less harmful the bite is likely to be, which is why children suffer far more seriously from snake bites than adults. A healthy person will also have better resistance against the poison.
Very few people actually die from snake bites in Britain, and though these bites can make some people very ill, there axe probably just as many cases of bites having little or no effect, as there are of serious illness.

单选题 Where do you know adders axe to be found?

单选题 If you are with someone who is bitten by an adder, you should ______.

单选题 We are told that adders are ______.

单选题 If an adder hears you coming, it will usually ______.