矣【yǐ】

矣 closes a classical sentence and says that the situation it describes holds now – it has come about, or it will once the condition is met. Its job is close to final 了, and like 了 it is not a past tense. Modern Chinese keeps it in quotations and in set phrases with an adjective or a short verb.

Set phrases

The common survivors are short: 足矣 "that is enough", 晚矣 "too late", 久矣 "for a long time now", and 此言差矣 "you are wrong there", which still turns up in speech as a mock-formal reply.

With a condition

In a classical "if A, then B" sentence, 矣 closes B and makes it a firm conclusion.

矣 or 了, not both

矣 is the classical 了, so a sentence ends with one or the other. 矣 is a statement, never a question marker.

• × 太晚了矣。 → 悔之晚矣。 / 太晚了。