～ている ②State of being, Has (have) done

The ている form describes an ongoing action or state. With verbs that describe actions over time, it functions like the English 'is...-ing,' but with state verbs, it means to be (or continue to be) in that state. For example, 食べている means 'is/am eating,' while 死んでいる means 'is/are dead' (not 'is dying').

The Verb + て form connects verbs or parts of a sentence. When an 'instantaneous' verb (one that expresses a single change in state) is combined with the existence verb いる in the ている form, it expresses an ongoing state. For example, 死んでいる means '(It) is dead.' With other verbs, ている conveys a meaning similar to the English 'is...-ing' (see ている①).

ている expresses an ongoing action or state. The ている② form is used with verbs indicating a single change in state, like 死んでいる ('is dead'), not an action. The ている③ form describes repeated or habitual actions, like 会社で働いている could mean ('I'm working for [that/this] company).

ている expresses an ongoing action or state. つづける attached to the verb stem expresses a similar meaning, but with a greater emphasis on the idea of continuation. For example, 増えている means that something is increasing or has increased, while 増えつづけている carries the additional nuance that it is continuing to increase.

The ている① form expresses completed actions or past states. Unlike English, verbs can directly modify nouns, similar to い-Adjectives. However, unless emphasizing a changing state, the past form (た) is usually preferred over ている when describing nouns. For example, 死んだネズミ ('a dead mouse') is more common than 死んでいるネズミ.