Section Three / Lesson Two - Using Accurate Prepositions
In this class, we are going to add numbers, percentages, and extra detail to our sentences from lesson one. Preposition choice is one of the most common errors in this type of question, and it is a great way to show the examiner that you have a 'good control of grammar' and can produce 'error-free sentences' as required in the IELTS Writing Task 1 Rubric (see here from more information).
We will use this simple line chart to look at the different uses of prepositions. It shows the number of cases of measles reported in the USA from 2010 to 2019.
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Every line chart has two axes, the X-axis, and the Y-Axis.
The X-axis goes along the bottom and shows time. The Y-axis goes up and down and shows what is changing. In this graph, the y-axis shows years and the x-axis shows the number of cases.
Describing the X axis - Time
One way in which you will have to add detail is to give the exact time or time period in which a change took place.
in - If you are describing a single point in time, we use the preposition 'in'. This is good for describing the beginning or end of a trend or describing peaks and troughs.
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In 2010, there were around 50 cases of measles.
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In 2011, there was a small peak.
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In 2019, there were nearly 1300 cases of measles.
between - most of the time when you are describing a change, you need to show two different times, one when the change started and one when it finished. There are two main prepositions we use for this. Firstly we can use: between start time and finish time.
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Between 2013 and 2014, there was a sharp rise in cases.
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The number of cases of measles grew sharply between 2013 and 2014.
by - This preposition shows the finishing time. You can only use this if the start time is clear from a previous sentence. We typically use this with past perfect tense, which we'll cover in the next lesson. by finish time
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By 2014, there had been a sharp rise in cases.
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The number of cases of measles had grown sharply by 2014.
over - A second way to show a duration of time is to use the preposition 'over'. We can use it with an article 'a, an, the', the amount of time, and finally the word 'period', or we can use 'the next' + the amount of time.
We use 'a' or 'an' the first time we describe this time period, and then use 'the' other every time.
The phrase will look like this: over a time phrase period or over the next time phrase.
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Over a one-year period, there was a sharp rise in cases.
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The number of cases of measure grew sharply over the one-year period.
Describing the Y axis - Other data
Now we shall look at the prepositions that we can use to add detail about the information given on the y-axis of a line chart.
at - We use this preposition if we are describing a single figure at a single point in time. This is often used to show the beginning or end of a trend, or to describe peaks and troughs. It often is used in conjunction with 'in + time'
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In 2011, there was a small peak at 220 cases.
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In 2019, there was the largest number of cases at 1300.
with - we also use this preposition to describe a single figure at a single point in time, but we must add a noun after the number describing what the number is.
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In 2010, measles wasn't very common with only around 70 cases.
70
1300
by - This preposition allows us to describe the difference between two numbers. If a number rises from two to ten, 10 - 2 = 8. The number has risen by 8.
However, we only use 'by' for verb phrases.
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Between 2018 and 2019, the number of cases rose by 900.
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1300 - 400 = 900
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of - 'of' shows the same as 'by', but can be used after a noun phrase. This needs to follow the noun phrase directly, not after the 'in + what changed' phrase.
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Between 2018 and 2019, there was a rise of 900 cases.​
1300
from/to - if you want to show both the beginning and starting number, we can use: from start time to finish time. This can be used for either a noun phrase or a verb phrase.
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Between 2018 and 2018, there was a sharp rise in measles cases from 400 to 1300.
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The number of cases of measles grew sharply from 400 to 1300 between 2018 and 2018.