I saw this two days ago in an online forum.

Problem:
The phrase “likely hood” — with the letter Y and a space in the middle — is a misspelling of a noun.

Explanation:
As with many other words that end with the letter Y, the “y” in a word such as “likely” must be changed to “i” when the suffix H-O-O-D is appended to it.

For fun, I searched Google for each of the following (with the quotation marks) and got about the indicated numbers of matches:

• “likelihood” — with the letter I in the middle — 31,400,000 matches
• “likely hood” — with the letter Y and a space in the middle — 130,000 matches

This tells me that Web authors have written the correct word vs. the incorrect phrase by a ratio of 242-to-1, which is excellent.

Still, the existence of some 130,000 Web pages with the phrase “likely hood” — with the Y and a space in the middle — is a bit depressing.

Solution:
“I know the likelihood of …”