Final answer:
Readers could figure out Roald Dahl wrote 'The Landlady' by recognizing his unique literary style, specifically his tone, diction, and syntax, as well as the narrative features, irony, and dark humor that pervade his writing.
Step-by-step explanation:
One way readers could figure out that Roald Dahl wrote 'The Landlady' is by analyzing the literary style and elements he utilizes in his writing. Dahl is known for his distinctive use of tone, diction, and syntax, which can be a clue to identifying his authorship. For instance, readers might recognize Dahl's style in the syntax of his sentences, which often include a particular order for dramatic effect, like in the quote: "By the time I am nearing the end of a story, the first part will have been reread and altered and corrected at least one hundred and fifty times. I am suspicious of both facility and speed. Good writing is essentially rewriting. I am positive of this." This meticulous attention to rewriting aligns with Dahl's authorship.
Moreover, while examining a literary piece, looking for patterns in the narrative features, such as the characters and settings, and the use of figurative language and dialogue, can signpost a work of Dahl's, who often imbues his stories with irony and dark humor. His thematic elements, alongside the careful choice of language and storyline construction, often differentiate his writing in the vast literary landscape, allowing a reader to identify his works among others.