Punctuation and special character removal in NLP - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to remove punctuation from the text using str.translate.

NLP

import string
text = "Hello, world!"
clean_text = text.[1](str.maketrans('', '', string.punctuation))
print(clean_text)

Drag options to blanks, or click blank then click option'

Astrip

Breplace

Ctranslate

Dsplit

Attempts:

3 left

💡 Hint

Common Mistakes

Using replace without a loop removes only one character at a time.

Using strip only removes characters from the start and end of the string.

The translate method with str.maketrans removes all punctuation characters from the string.

2fill in blank

medium

Complete the code to remove all characters that are not letters or spaces using a list comprehension.

NLP

text = "Hello, world! 123"
clean_text = ''.join([c for c in text if [1] or c == ' '])
print(clean_text)

Drag options to blanks, or click blank then click option'

Ac.isalpha()

Bc.isdigit()

Cc.isupper()

Dc.isspace()

Attempts:

3 left

💡 Hint

Common Mistakes

Using isdigit() keeps numbers instead of letters.

Using isspace() only keeps spaces, removing letters.

The isalpha() method checks if a character is a letter. We keep letters and spaces only.

3fill in blank

hard

Fix the error in the code to remove punctuation using regex.

NLP

import re
text = "Hello, world!"
clean_text = re.sub([1], '', text)
print(clean_text)

Drag options to blanks, or click blank then click option'

A'[a-zA-Z]'

B'[!?,.]'

C'[0-9]'

D'[^a-zA-Z ]'

Attempts:

3 left

💡 Hint

Common Mistakes

Using '[a-zA-Z]' removes letters instead of punctuation.

Using '[0-9]' removes digits only, not punctuation.

The regex '[^a-zA-Z ]' matches any character that is NOT a letter or space, so it removes punctuation and digits.

4fill in blank

hard

Fill both blanks to create a function that removes punctuation and converts text to lowercase.

NLP

import string

def clean_text(text):
    return text.[1](str.maketrans('', '', string.[2])).lower()

Drag options to blanks, or click blank then click option'

Atranslate

Breplace

Cpunctuation

Dwhitespace

Attempts:

3 left

💡 Hint

Common Mistakes

Using replace instead of translate does not remove all punctuation at once.

Using string.whitespace removes spaces, which we want to keep.

The translate method removes all punctuation characters defined in string.punctuation. Then lower() converts text to lowercase.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that maps words to their cleaned versions without punctuation and in lowercase.

NLP

import string
words = ['Hello!', 'World?', 'Test.']
clean_words = {word[1]: word.[2](str.maketrans('', '', string.[3])).lower() for word in words}
print(clean_words)

Drag options to blanks, or click blank then click option'

A.lower()

Btranslate

Cpunctuation

D.strip()

Attempts:

3 left

💡 Hint

Common Mistakes

Using strip removes only whitespace, not punctuation.

Not converting to lowercase causes inconsistent keys.

The dictionary comprehension uses translate with string.punctuation to remove punctuation, then lower() to convert to lowercase.