Final answer:
To determine the proper time signature for a piece in trochaic meter, one typically considers 2/4 time, which naturally fits the stressed-unstressed pattern of this poetic meter.
Step-by-step explanation:
Deciding the time signature for a piece of music involves considering the rhythmic structure and how the piece is naturally divided into beats. The given phrase, "The curfew tolls the knell of parting day," shares a rhythm similar to the example given, "Tiger tiger burning bright," known to be in trochaic meter. This meter consists of a stressed syllable followed by an unstressed one, typically annotated as '/ x' where the '/' represents a stressed syllable and the 'x' an unstressed one.
The time signature that commonly fits trochaic meter is 2/4 time, where there are two beats per measure, and the quarter note gets one beat. This time signature matches the natural emphasis pattern of the trochaic meter in the phrase provided. However, other time signatures like 4/4 or 3/4 could also be possible, depending on the full musical context and how the composer wants the piece to be phrased.