Arrive early: Music Hall (3,400 seats) is usually packed for the opera. When the curtain goes up, you won't be seated until the first pause - which could mean an hour-long wait.
What to wear: Anything goes. You'll see tuxes and gowns, especially on opening night. But most men wear suits or go business casual; women wear summer dresses or pants. Wraps are big: it can be cool in Music Hall.
When to clap: Opera is like jazz. When a musician wows with a sensational solo, clap. Likewise, when an opera singer finishes a big aria, it's OK to clap, stand yell "bravo" (for men), "brava" (for ladies) or "bravi" (for everybody).
Opera no-nos: Cell phones or pagers left on; noisy candy wrappers; camera flashes.
How long is it? The operas range from short one-acts - The Emperor of Atlantis is 55 minutes - to Don Giovanni and Carmen, each lasting about 21/2 hours.
Intermission: There is one 25-minute intermission.
Food at Music Hall: Plan to eat dinner before or after the opera. You can get soft drinks, sparkling wine, Graeter's ice cream and Divine's Chocolates at concession stands. Espresso and sandwiches are sold in the north lobby bar.
Prelude dinners: Four courses at 6 p.m. in Corbett Tower, presented by the Opera Guild ($29; reservations 241-2742).
Bel canto: Beautiful singing, marked by beauty of tone and legato (smooth) phrasing.
Buffo: The comic role, often given to a bass.
Cadenza: A flourish where a singer sings fast, high or difficult passages to show what she or he can do.
Coloratura: Elaborate ornamentation of a melody, such as trills and runs. A coloratura soprano is one whose voice is high, light and agile.
Dynamics: Volume in music, such as piano (soft), forte (loud) and crescendo (getting louder).
Libretto: Italian for "little book," it's the written text.
Opera-comique: French opera with lighthearted subject matter. Usually (but not always) includes spoken dialogue.
Overture: The instrumental introduction to the opera. It previews the opera's musical themes and sets the mood.
Recitative: Speech-singing in which the singer, who needs to get through a lot of text quickly, semi-chants the words.
Surtitles: The English translation projected across the top of the stage.
Trouser role: A male role played by a female.
Verismo: Realism depicting the violent or seamy side of life, such as murder or suicide.