た / ている

A verb describes a noun by standing straight in front of it, where English uses a relative clause after it: "the book that I bought". There is no word for "that" or "who". In the た-form the action is done; in the ている form it is going on, or its result still holds.

Nothing goes between the verb and the noun – no の, no な.

• × 昨日買ったの本 → 昨日買った本

The clause can carry its own subject, object and time words, all in front of the noun, and the noun can then play any part in the main sentence.

が inside the clause, not は

The subject of the describing clause takes が, or の, never は. は would make it the topic of the whole sentence.

• × 母は作った料理 → 母が作った料理

ている before a noun

ている describes an action in progress, or a state that resulted from an action and still holds. With すむ住む, けっこん結婚する or かける (glasses), it is a state, not something happening right now.

た before a noun is not always past

The た-form says the action is done by the time of the main verb, not necessarily before now. It also turns some verbs into plain descriptions: こわれた壊れたかさ傘, "a broken umbrella".