Introduction

Labeling words in a sentence with their appropriate grammatical categories, such as nouns, verbs, adjectives, or adverbs, is known as part-of-speech (POS) tagging. This technique enables us to understand a sentence’s syntactic structure and determine a word’s meaning about other words. For instance, in the sentence “The cat sat on the mat,” the words “cat” and “mat” would be tagged as nouns, “sat” as a verb, “the” as a determiner, and “on” as a preposition. By assigning each word to a grammatical category, we ensure that we prepare our data for later analysis, such as text classification, sentiment analysis, and information retrieval. Here are some common POS tags.

Common POS Tags

Short form	Full form	Meaning	Example
JJS	Adjective	Superlative form of an adjective	“best” (It’s the best option.)
RB	Adverb	Modifies a verb, adjective, or other adverbs	“quickly” (He ran quickly.)
NUM	Numeral	Represents numbers and quantities	“three” (There are three apples.)
PRP	Pronoun	Replaces a noun or noun phrase	“she” (She is going to the park.)
PUNCT or , or .	Punctuation	Includes various punctuation marks	“.” (Period at the end of a sentence)
VERB	Verb	Expresses actions, events, or states	“run” (They run every morning.)
MD	Modal Verb	Expresses possibility, necessity, or permission	“can” (He can swim.)
NN	Noun	Represents a person, place, thing, or idea	“city” (The city is beautiful.)
NNP	Proper Noun, Singular	Singular proper noun	“Alice” (Alice Johnson.)
NNPS	Proper Noun, Plural	Plural proper noun	“Smiths” (The Smiths band.)
IN	Preposition	Shows a relationship between a noun/pronoun and another word in the sentence	“in” (He is in the room.)
CD	Cardinal Digit	Numerical digits	“2023” (The year 2023.)
DT	Determiner	Specifies or limits a noun	“the” (He used the book.)
VBG	Verb, Gerund or Present Participle	Represents an action or process in progress	“running” (He is running.)
JJ	Verb, 3rd Person Singular	Indicates an action performed by the subject in the third person singular	“runs” (She runs fast.)
VBN	Past Participle Verb	Indicates an action that has occurred in the past and is often used with auxiliary verbs	“eaten” (He has eaten lunch.)

About This Course

Introduction To Text Preprocessing

Regular Expressions

Irrelevant Text Data

Basic Text Preprocessing Techniques

Indexing

Text Transformation

Text Representation

Text Feature Engineering

Advanced Text Preprocessing

N-grams

Text Classification of Customer Reviews

Conclusion

Text Classification Using PyTorch

Part-of-Speech Tagging

Introduction

Common POS Tags