Pronoun Reference to Nouns

You cannot use a pronoun to replace a noun if the replacement is not clear

For example:

• William said that John said that he had won the bingo game's biggest prize. (Who is the "he" William or John?)
• William is a liar. The most recent problem we had with William was when he denied knocking the ladder into the staircase and cracking it. (What cracked, the ladder or the staircase?)
• I also know that last year, when we had the rash of petty thievery, when William had the cash flow problem, and when he was visiting us, he picked up the crystal paperweight, played with the silver letter opener, and then put it into his pocket. (What did William steal, the paperweight or the letter opener?)

In cases such as these, you need to clarify the sentence by using a noun instead of a pronoun. Remember, never substitute a pronoun for a noun if the person, place, or thing to which the pronoun refers is unclear.