The phrase 'เป็นต้นไป (pen dton bpai)' is used in Thai language to indicate the continuation of an action, time, event, or condition from a certain point onwards. It is equivalent to the English terms 'onwards', 'and so forth', or 'etcetera'. This phrase is often placed after a specific point in time, number, or event to denote that everything following is included or continues in a similar manner.