What is the difference between ambiguous reference and ambiguous sentence?

Unknown reference means that pronouns are used in a sentence, but the things they refer to make people unable to determine the object they refer to, which leads to ambiguity.

Pronouns are divided into personal pronouns (such as: I, you, he, she, it, us), demonstrative pronouns (such as: this, that, here, there) and interrogative pronouns (such as: who, where).

Sentence ambiguity refers to the loss of sentence certainty, such as ambiguity caused by polysemous words, a series of ambiguous sentences with unknown references and subjects.