Final answer:
Victorien Sardou is the French playwright known for his well-made play formula.
Step-by-step explanation:
The French playwright who wrote over 300 plays in a variety of genres and is best known for his well-made play formula is Victorien Sardou. He was a prominent figure in French theatre during the late 19th century and early 20th century. Some of his notable works include Adrienne Lecouvreur and The Glass of Water. Sardou's well-made play formula emphasized a tightly constructed plot, realistic dialogue, and unexpected twists.
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