[MUSIC] English for Teaching Purposes. Describing Graphs. >> You probably know by now that presenting data in sparkling colors does help. [MUSIC] Graphs are a great way to present data, because they represent numbers well, graphically. [MUSIC] They also help make the relation among numbers more understandable. And guess what, easier to remember. Your students will definitely appreciate looking at numbers plotted into graphs rather than at raw numbers. There are many kinds of graphs, of course. You know exactly what kind of graph suits your classes better. What we'll do on this video is study the most common types of graphs and study the language we need to present them. Let's get started with a simple classification of graphs. Line and bar charts are greatly popular as they help represent the interaction among different variables. Pie charts are quite efficient to present factions and percentages. Some people will argue that tables also help present information in a more digestible way. Of all these graphs, perhaps the one that poses the biggest challenge is the line chart. Their beauty lies in the fact that every little line going up or down or just sliding straight can be meaningful and is thus susceptible to a description. You'll see what I mean in a sec. Before getting into the business of explaining how to describe the lines representing data, let's look at the axes. Typically, line graphs will have a horizontal axis, conventionally understood as the X axis, and a vertical axis, or Y axis. The lines clearly represent the results of the interaction between the two axes. Nowadays we tend to use a lot of color in graphs because we can. The equipment we use allows for that. But we might choose to differentiate several different lines using solid lines, broken lines, or dotted lines. If there are several lines dancing around your graph, remember to identify which one you're referring to when describing movements or segments. This is the way you would do it. The dotted, or red line, or the dotted red line represents x. We can see that it plunges over there, but then it picks up right over there. When lines describe a dramatic upward movement, we will call it a rise, an increase, or a growth. Dramatic downward movements will be described by the opposite words. So a fall, a decrease, or a decline. We can also describe the movement itself. So, rise, go up, climb, versus fall, plummet, plunge, drop, go down, or collapse. There are some expressions that have the same meaning as the verbs, but they are more metaphorical. Shoot up, sky rocket, take off, or hit a high and, take a plunge. Hit a low or bottom out. In fact, what's really interesting about movements like this is that they are very abrupt. And so they can be described using qualifiers. Dramatic, sharp, abrupt, significant, noticeable, sudden. Lines can also climb or decline in less acute ways. To describe such movements we would use a different set of qualifiers like slight, slow, relative, faint, minimal or modest. When a line moving upwards reaches it's highest point, we call it a peak. We can also use a word as a verb, as in, the increase in the production of m peaked at r. And the opposite point would be called a trough. In some cases the lines will stabilize, drawing a straight horizontal line. We will call it stable, steady, constant, flat. If you prefer verbs, stabilize, flatten out, level off, remain steady, are adequate. These two kinds of graphs tend to represent data that are more static. A bar chart is made of bars, and you should refer to them as such. Pies have slices, and well, that's how they should be called. The realities represented by both graphs will reflect expansion, shrinking, increase, reduction, growth and decline. The bars and slices, are usually compared using expressions of comparison that we have already dealt with on a separate video. Just, make sure to check it. When a bar graph represents the evolution of a phenomenon, we can use expressions similar to the ones that describe line graphs. For example, you can identify an increase between the amount of rain registered in a period of a year, by saying. Rain increased dramatically in the months of March and April. And then, drastically plummeted in May. Between June and August it remained at a constant low. It slightly rose from September to November. And it became snow as soon as December arrived. There are a few other language details that you should remember when describing. One of' em is that when dealing with percentages, you don't add articles before the numbers. So you should say 80% of the subjects chose x whereas 20% chose y. Also, the preposition that accompanies increases and decreases is by bacteria colonies grew by 3%. You have plenty of words and expressions to choose from. That means you can vary the expressions you use in class as you gain more confidence. And that's all we have for you on graphs. See you next time. [MUSIC]