Past time prefix (เมื่อ)

Placing Events in the Past

To specify that an event happened at a particular time in the past, use the prefix เมื่อ. Place it directly before time nouns.

You will often see it paired with words like วานซืน (the day before yesterday) or ปีกลาย (last year) to anchor a sentence firmly in the past. These time phrases can appear at either the beginning or the end of the sentence.

Stages of Life

You can also use เมื่อ before nouns that describe stages of life, such as วัยเด็ก (childhood) or วัยรุ่น (teenage years). This translates naturally to "in my childhood" or "when I was a teenager."

Historical Eras

To talk about specific historical periods, use the word สมัย (era or times) right after เมื่อ.

By placing the name of a historical period or a major event—like อยุธยา (Ayutthaya) or สงคราม (war)—after เมื่อ สมัย, you create phrases meaning "during the Ayutthaya era" or "during wartime."

Decades and Centuries

When discussing the broader timelines of history, use ศตวรรษ (century) and ทศวรรษ (decade). You can combine these with เมื่อ and modifiers meaning "last" or "ago" to talk about the distant past.