Why "under going" is incorrect and how to use "undergoing" properly

What kind of error is it?

Spelling and word usage error

Why do people make this mistake?

The error "under going" is typically made due to the confusion between the adverb "under" and the noun "undergoing". The correct word "undergoing" is often mistakenly split into two separate words. This can happen because people try to form it analogously like separately using "under" followed by another verb or noun.

What is correct?

The correct form is the single word "undergoing", which means experiencing or being subjected to something, such as a process or change.