Is it proper to end a sentence with the word of?

It's generally considered not proper to end a sentence with the word "of" in formal writing. This rule comes from a grammatical principle called "prepositional phrase placement," which suggests that prepositions (like "of") should be followed by their objects and not placed at the end of a sentence.

However, there are exceptions and situations where ending a sentence with "of" is acceptable:

* Informal writing: In informal writing, such as casual conversations, emails, or social media posts, ending a sentence with "of" is often acceptable and even common.

* Emphasis: Ending a sentence with "of" can sometimes be used for emphasis or to create a particular rhythm or tone.

* Poetic license: In poetry, grammatical rules are often bent for artistic effect, and ending a sentence with "of" might be used for rhyme or meter.

Example:

* Formal: "The book was full of interesting information."

* Informal: "The book was interesting, full of information."

Ultimately, the best approach is to consider the context and your audience. In formal writing, it's generally safer to avoid ending sentences with "of." In informal settings, it's often more acceptable.