Once you understand what is counts as a simile and what counts as a metaphor it would become more easier.
A simile is a comparison of at least two things using the words "like" or "as".
For example, the usage of a simile can include:
Tom is like a mountain goat, leaping from one rock to another.
Note the comparison of Tom to a mountain goat, and the usage of "like", or being similar too.
Another example can be:
James was as brave as a lion, strong as a bear, leapt like a gazelle, and as smart as Einstein.
Note the comparison of James to many different animals as well as a famous person.
The next thing that you should be learning is Metaphor, which is kind of related to similes.
Metaphors is a comparison, but without using the words "like" or "as"
For example, the usage of a metaphor can include:
Her long hair flowed down like a river.
While "like" or "as" was not used, her hair was compared to a river.
When you understand this concept it would be very very useful, especially when writing essays. Most of the time you may need to compare things, such as products, ideas/beliefs, and even different civilizations within a time period (specifically in history class). Understanding how to use similes & metaphors can help enhance your writing.
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