Rhetorical Device: Apposition

The 'Beatrice' example cited above does not have punctuation, which implies that it is a restrictive appositive, which in turn means that the speaker must have more than one daughter. The concepts of restrictive and unrestrictive appositives are detailed in the following sections.

Restrictive

A restrictive appositive gives information that is essential to identify the noun/noun phrase that it describes. In other words, if the appositve is removed from the sentence, it will alter or obscure its meaning. Restrictive appositives must not use punctuation. For example:

The space telescope TESS was designed to search for exoplanets using the transit method and was launched on 18 April 2018.

Without the appositive, we wouldn't know which space telescope was being referred to. Therefore the appositive is essential and so it is rendered without commas (or other punctuation).

Nonrestrictive

A nonrestrictive appositive gives information that is nonessential to identify the noun/noun phrase it describes. This could be considered as bonus information. This type of appositive must be seperated from the surrounding text using punctionation, normally commas, although parenthesis or em dashes (long dashes) can be used. Colons can also be used if the appositive occurs at the end of the sentence. It is also possible to have an appositive at the beginning of a sentence. Here are some examples (along with some knowledge about a gentle species of great ape): 

• Mountain gorillas — highly social animals — live in relatively stable, cohesive groups held together by long-term bonds between adult males and females.
• Mountain gorillas (close relatives of humans) are susceptible to human illnesses.
• The mountain gorilla, a subspecies of the eastern gorilla, is listed as endangered by the IUCN with just over 1000 in the wild and none in captivity.
• Uganda's Bwindi Impenetrable National Park is home to a population of mountain gorillas: about 400 individuals.
• Primarily a herbivore, the mountain gorilla eats leaves, shoots, stems, bark, roots, flowers, fruit, and very occasionally small invertebrates.

More examples

..the United States must always have the unshakable trust of our ally Israel.Leon Panetta, "Address to the American-Israel Political Affairs Committee" (6 March 2012)

Ulysses, a novel of ordinary lives, is organised around Homer’s Odyssey – advertising agent Bloom being Odysseus to Molly, his Irish Penelope. It insists on the mundane – lavatory visits, smelly cheese sandwiches – while being extraordinary in its methods: different styles from different literary periods jostle for control. The Guardian - Editorial, "The Guardian view on James Joyce’s Ulysses: a 100-year-old masterpiece" (10 June 2022)

In a sense we've come to our nation's capital to cash a check. When the architects of our republic wrote the magnificent words of the Constitution and the Declaration of Independence, they were signing a promissory note to which every American was to fall heir. This note was a promise that all men, yes, black men as well as white men, would be guaranteed the "unalienable Rights" of "Life, Liberty and the pursuit of Happiness." It is obvious today that America has defaulted on this promissory note, insofar as her citizens of color are concerned. Martin Luther King, "I Have a Dream" (28 August 1963)

Second, as the most adamantine rock gives way under the constant dripping of water, so the opposition to woman suffrage in our own country has slowly disintegrated before the increasing strength of our movement. Turn backward the pages of our history! Behold, brave Abbie Kelley rotten-egged because she, a woman, essayed to speak in public. Carrie Chapman Catt, "The Crisis" (7 September 1916)