sed substitution in Linux CLI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to replace the first occurrence of 'apple' with 'orange' in the input text.

Linux CLI

sed '[1]/apple/orange/' file.txt

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

Ad

By

Cs

Dp

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'y' instead of 's' which is for transliteration, not substitution.

Using 'd' which deletes lines, not substitutes text.

The 's' command in sed is used for substitution. Here, it replaces 'apple' with 'orange'.

2fill in blank

medium

Complete the code to replace all occurrences of 'cat' with 'dog' in the input text.

Linux CLI

sed '[1]/cat/dog/g' file.txt

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

As

Bd

Cy

Dp

Attempts:

3 left

💡 Hint

Common Mistakes

Omitting the 'g' flag, which replaces only the first occurrence per line.

Using 'd' which deletes lines instead of substituting text.

The 's' command with the 'g' flag replaces all occurrences of 'cat' with 'dog' in each line.

3fill in blank

hard

Fix the error in the sed command to replace 'blue' with 'red' only on lines containing 'sky'.

Linux CLI

sed '/sky/ [1] blue/red/' file.txt

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

Ad

Bs

Cp

Dy

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'd' which deletes lines instead of substituting text.

Omitting the 's' command causing syntax error.

The substitution command 's' must be used after the address '/sky/' to replace 'blue' with 'red' only on matching lines.

4fill in blank

hard

Fill both blanks to replace 'dog' with 'cat' only on lines starting with 'Pet'.

Linux CLI

sed '[1]/^Pet/ [2] dog/cat/' file.txt

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

A-n

Bs

Dp

Attempts:

3 left

💡 Hint

Common Mistakes

Not using '-n' causes all lines to print, not just modified ones.

Using 'p' instead of 's' for substitution.

The '-n' option suppresses automatic printing, and 's' performs substitution on lines starting with 'Pet'.

5fill in blank

hard

Fill all three blanks to replace 'apple' with 'orange' globally and print only changed lines.

Linux CLI

sed '[1]' file.txt | sed '[2]/apple/[3]/orange/gp'

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

A-n

Cs

Attempts:

3 left

💡 Hint

Common Mistakes

Omitting '-n' causes all lines to print.

Using 'd' or 'p' incorrectly instead of 's' for substitution.

The first sed suppresses output with '-n'. The second sed uses '-n' and 's' with 'gp' to substitute globally and print changed lines.