Translation guide
In Japanese, 'first half' is commonly expressed using words like 前半 (ぜんはん) or 上半期 (かみはんき), depending on context. The choice depends on whether you're referring to a general period, a game, a year, or a specific event.
first half
Most common translation. Use 上半期 for fiscal/business years.
Referring to the first half of a time period, event, game, or sequence.
The most common and versatile word for 'first half'. Used for games, years, centuries, movies, etc.
The first half of the game was a close match.
I was born in the first half of the 20th century.
Specifically the first half of a fiscal or calendar year. Common in business contexts.
Sales in the first half of the year were strong.
Emphasizes the first half as a portion or share. Often used when dividing something into two equal parts.
I ate the first half of the cake.
Literally 'the first half'. More colloquial and can be used for physical objects or time.
The first half of the book was boring.
Specifically the first half of a sports game or competition.
前半 (ぜんはん) is general-purpose for any period or event. 上半期 (かみはんき) is specifically the first half of a business or calendar year. Do not use 上半期 for games or movies.
Do not translate 'first half' word-for-word as 最初の半分 (さいしょのはんぶん) in most contexts. While understandable, it sounds unnatural. Use 前半 instead.
その映画の前編は昨日公開された。
The first half of the movie was released yesterday.