Perfect indefinite aspect is a perfect form of a verb, formed with the help of the auxiliary verb "have" in the form of the indefinite aspect and the notional verb in the form of participle II:

1. The perfect aspect in the present tense: I have spoken.
2. The perfect aspect form in the past tense: I had spoken.

Usually in practical grammars “perfect infinitive forms of the verb” are simply called “perfect forms of the verb”. Hence, for example, “present perfect (tense)” means “present perfect-indefinite (tense).”

In general, the perfect form of a verb is used to express an action that precedes another action or some point in time, and this action is associated with this action or time:

• I have read the newspaper by now. I can give it to you. (i.e. the fact that I can give you this newspaper is the result of the fact that I have already read it);
• I had read the newspaper and was watching TV when you came. (indicates that one event had already ended when another event was happening: when you came, I was no longer reading, but watching TV);
• I have spoken to him today. (the event is associated with the period in time in which it is spoken about);
• I will have come home by the time the TV show starts. (one event will already have taken place when the other begins);
• She doesn't know I have left. (She doesn’t know that I’m not (now) present.)

For more information on the use of perfect-indefinite forms of the verb, see "Present Perfect" and "Past Perfect".

The perfect aspect form of intransitive verbs can also be formed using the verb "be" :

• The guests are all gone. ⇔ The guests have all gone.
• What falls, is fallen. ⇔ What falls, has fallen.
• The sun is risen. ⇔ The sun has risen.

Formed with the verb "be", the perfect is used if the achieved state is emphasized, rather than the action to achieve it:

• He is gone. – He is not here. / He died.
• But: He has gone into town for stores.

In modern English, the formation of the perfect with the verb "be" is almost not used and is replaced by the verb "have". And for example the sentence "The sun is risen." you are unlikely to see in modern text or conversation, it sounds poetic and archaic, but some words, such as "fall", "go" and "grow" can still be used in modern English when forming the perfect with the verb "be":

• All our children are grown up.
• All hope is gone.
• He is fallen asleep on the sofa.