The verb sein means "to be" and is used to describe identity, state, time, existence, and more. It is an irregular verb, so its forms must be memorized. It also serves as an auxiliary verb for forming some tenses.
Roots and Patterns
- Present tense forms come from sei- (ich, er/sie/es), sind (wir, sie), and seid (ihr), plus the irregular bin for ich and bist for du.
- Past participle is gewesen.
- Simple past (Präteritum) forms use the root war-.
- The verb changes form depending on person, number, and sometimes mood.
Which irregular present tense forms of sein must be memorized for the subjects ich and du?
ich bin, du bist
The irregular present tense forms are ich bin and du bist. Other forms follow more regular patterns (sind, seid, ist).
Usage
- Sein is used for describing states, identities, times, and existence.
- It functions as an auxiliary verb in the perfect tense for some verbs, especially those indicating movement or change of state.
- It appears in many set phrases and idiomatic expressions.
Which of the following is true about using sein as an auxiliary verb in the perfect tense?
sein is the auxiliary for verbs indicating movement or change of state, but sein itself uses haben
Verbs like gehen and kommen use sein as the auxiliary in the perfect tense (e.g., Ich bin gegangen), but sein itself uses haben (e.g., Ich habe gewesen), though this form is rare.
Conjugation Tables
Present Tense (Präsens)
| Person | German Example | English Example |
|---|---|---|
| ich bin | Ich bin müde. | I am tired. |
| du bist | Du bist Lehrer. | You are a teacher. |
| er/sie/es ist | Er ist zu Hause. | He is at home. |
| wir sind | Wir sind Freunde. | We are friends. |
| ihr seid | Ihr seid fertig. | You (pl.) are finished. |
| sie/Sie sind | Sie sind glücklich. | They are happy. |
Simple Past (Präteritum)
| Person | German Example | English Example |
|---|---|---|
| ich war | Ich war krank. | I was sick. |
| du warst | Du warst spät. | You were late. |
| er/sie/es war | Sie war hier. | She was here. |
| wir waren | Wir waren müde. | We were tired. |
| ihr wart | Ihr wart laut. | You (pl.) were loud. |
| sie/Sie waren | Sie waren weg. | They were gone. |
Past Participle and Perfect Tense
- Past Participle: gewesen
- Present Perfect (Perfekt) uses sein as an auxiliary (e.g. Ich bin gegangen) but sein itself uses haben (e.g. Ich habe gewesen — though this is rare):
Examples and Usage
Descriptions and States
Use sein to describe people, things, or situations.
- Ich bin müde. (I am tired.)
- Das Wetter ist schön. (The weather is nice.)
Identity and Profession
Use sein to state who someone is or what their role/profession is.
- Du bist Lehrer. (You are a teacher.)
- Sie ist Studentin. (She is a student.)
Location and Time
Use sein for telling time and sometimes location.
- Es ist zehn Uhr. (It is ten o’clock.)
- Wir sind zu Hause. (We are at home.)
Existence and Presence
- Es ist niemand da. (There is no one there.)
- Ist jemand im Zimmer? (Is someone in the room?)
Auxiliary Verb
- Ich bin gegangen. (I have gone.)
- Wir sind gekommen. (We have come.)
I have gone. (Perfect tense)
Ich bin gegangen.
Verbs of movement like gehen use sein as the auxiliary in the perfect tense: Ich bin gegangen.
Irregularities and Tips
- Sein* is highly irregular. Memorize the main forms.
- Pay attention to context: sein can indicate identity, state, time, or existence.
- In the perfect tense, sein is always used with sein as the auxiliary, but sein itself uses haben.
- Be careful with the subjunctive mood forms (würde sein, wäre, etc.) for expressing wishes or hypotheticals.
Which auxiliary verb does sein itself use in the perfect tense?
haben
Sein itself uses haben as the auxiliary in the perfect tense, though forms like Ich habe gewesen are rare.
Summary
- Sein = "to be"; describes states, identities, times, existence.
- Irregular forms: ich bin, du bist, er/sie/es ist, wir sind, ihr seid, sie sind
- Simple past uses the root war- (ich war, du warst, etc.).
- Past participle is gewesen.
- Functions as both a main verb and auxiliary.
Flashcards (1 of 12)
- Person: ich bin
- English Example: I am tired.
Last updated: Wed Jun 18, 2025
