托福考试

【单选题】
{$mediaurl} What is the discussion mainly about
A、Regions that are known for their maple syrup industries.
B、The production of maple syrup.
C、The process by which maple trees produce sap.
D、The history of the maple syrup industry.
网考网参考答案：B
网考网解析：
[解析] 6-11 [Professor (female)] Q7 Class, I have a question for you. What’s a sugar bush [Student A (male)] A sugar bush isn’t that a species of bush that you can get, um, sugar water out of For making syrup [Student B (male)] No, no...it’s not a bush. A sugar bush is a, a grove of maple trees, and those trees are used to produce the maple syrup. [Professor] You got it. Q6 And that’s what I want to talk to you about today: maple syrup production. Now, some of you are probably really familiar with the process. Especially if you’re from somewhere like Quebec or Vermont...or anywhere else in northeastern North America. ’Cause that’s a center for maple syrup production. Canada makes the vast majority of the world’s maple syrup: 80%. Vermont is the largest producer in the United States, followed by Maine and New York. But even if you don’t live in the Northeast, you still might’ve had the opportunity to see maple syrup being made, because it can basically be produced wherever maple trees grow. [Student A] But are some types of maple trees better for making syrup than others There are lots of types of maple trees, aren’t there [Professor] Yes. That’s a good point. Most of the time, maple syrup is made from sugar maples or black maples--since their sap has a pretty high sugar content. About 2%. Sap--you know what that is, right It’s the fluid that runs through the vascular system of plants. It’s a mixture of sugar, water, salts, and minerals. And it’s the raw form of maple syrup. So how does the process work Well, maple syrup production usually happens in early spring.This could be February, March, or April, depending on the region and the weather conditions. Q9(A) Basically, you need to have nights where the temperature drops to below freezing and then days that are pretty warm. Conditions like these cause the sap in maple trees to start running. When the temperature drops below freezing, water gets taken in from the soil.Then when the temperature rises above freezing, the sap starts to flow. So when maple syrup producers drill a hole in the trunk of a maple tree, the sap will run right out of it. It usually flows for a period of about, um, 4 to 6 weeks. I already mentioned which species of maple trees are best to tap, but there’re other considerations as well. Experts look for trees that are, um, out in the open. Trees that don’t have to deal with a lot of competition from other trees nearby. These kinds of trees produce a lot more sap than trees that grow in crowded forests. Um, for example, 15 to 20 gallons of sap in a season compared to just 10 gallons a season for forest-grown trees. Once the trees have been selected, there’s some setting up that has to be done. Q8 It really only takes some basic equipment like Q8(A) a bucket for collecting the sap and Q8(B) a spout for directing it as it runs out of the tree. Of course, larger operations use more sophisticated equipment like, um, plastic tubing and pipelines to make the process more efficient. But the basic idea doesn’t change.You drill a hole in the trunk of the tree, insert the spout, and position the container to collect the sap as it runs out. Oh, and if you’re doing this year after year, it’s important to remember that you have to drill a new hole every time... 查看试题解析出处>>