The line graphs show 
production
 levels of three main fuels in the United Kingdom, consisting Use synonyms
Use synonyms
petroleum
, coal and natural gas. The data was preserved from 1981 to 2000.
Change preposition
of petroleum
Overall
, Linking Words
Petroleum
 Use synonyms
have
 the highest Change the verb form
has
production
 among all. Use synonyms
Although
 have Linking Words
fluctuation
 trend, the Correct article usage
a fluctuation
production
 of Use synonyms
petroleum
 is still dominating. The Use synonyms
production
 Use synonyms
on
 natural gas was inclined Change preposition
of
in
 1981 to 2000. On Change preposition
from
other
 hand, Correct article usage
the other
coal's
 Change noun form
coal
production
 Use synonyms
had 
declined through those years.
Unnecessary verb
apply
According to
 the ghraphs, Linking Words
petroleum
 Use synonyms
production
 is inclining Use synonyms
in
 1981 to 1984, but it was stagnant until 1987. After that period, the Change preposition
from
production
 was Use synonyms
decrease
 until 1990. Wrong verb form
decreased
However
, it can be seen that it slowly Linking Words
increase
 until 2000.
On Wrong verb form
increased
other
 hand, natural Correct article usage
the other
gas'
 Change noun form
gas
production
 was stagnant from 1981 to 1990, but it significantly Use synonyms
increases
 after that, and Wrong verb form
increased
reach
 Wrong verb form
reached
to 
100 Energy Units in 2000. Change preposition
apply
Nonetheless
, Linking Words
the 
Correct article usage
apply
coal's
 Change noun form
coal
production
 was stagnant from 1981 to 1983Use synonyms
,
 and Remove the comma
apply
decreases
 sharply in 1984. Despite the Wrong verb form
decreased
production
 Use synonyms
was increase
 until 1986, it Change the verb form
increased
continues
 to decline to below 40 Energy Units in 2000.Wrong verb form
continued