If you have a text, for example retrieved from a database like LION, you can run that through a text analysis tool and get information or see patterns that may otherwise be difficult to spot.
Concordance tools - search for a word or phrase and see all instances in your text, displayed with a limited amount of context
Other tools/sets of different tools
Word class taggers - a tool that will analyse the words in your text and mark this part of speech.
These are two taggers available for free online:
The CCG POS tagger results look like this, with a key below the extract:
Poe, Edgar Allan, 1809-1849: The Tell-Tale Heart (Penguin Classics)
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