Ich prüfe jede Frist, sei es die Leihfrist oder die Abholfrist.

Sei es ... oder ... is a set expression meaning something like:

• whether it be ... or ...
• be it ... or ...
• whether it is ... or ...

It introduces examples or alternatives under a more general statement.

So in Ich prüfe jede Frist, sei es die Leihfrist oder die Abholfrist, the speaker first says I check every deadline/period, and then adds two possible kinds of deadline: the loan period or the pickup period.

This expression is a bit more formal or literary than the most everyday alternatives.

Because sei is the Konjunktiv I form of sein.

Here, German uses sei es in a special formulaic expression. It does not sound like normal present-tense es ist. Instead, it has a slightly elevated, abstract sense: be it ...

Compare:

• es ist = it is
• sei es = be it / whether it be

So this is not just an ordinary verb choice; it is part of the fixed expression sei es ... oder ....

It is largely a fixed expression.

Learners should treat sei es ... oder ... as a ready-made pattern. It is commonly used to introduce alternatives or examples after a general statement.

Pattern:

• ..., sei es A oder B.

Examples:

• Er hilft immer, sei es mit Geld oder mit Zeit.
• Wir müssen jede Möglichkeit prüfen, sei es Plan A oder Plan B.

You do not normally use sei es in casual speech as freely as ordinary verb forms. It is best learned as a chunk.

German often uses the singular with jede to mean every single ....

So:

• jede Frist = every deadline / each deadline
• alle Fristen = all deadlines

Both can work, but they are not exactly the same in tone:

• Ich prüfe jede Frist emphasizes each individual one.
• Ich prüfe alle Fristen emphasizes the whole group.

In your sentence, jede Frist fits well because the speaker is talking about any type of deadline one by one, and then gives examples of such deadlines.

Jede Frist is in the accusative case because it is the direct object of prüfen.

The verb prüfen takes a direct object:

• Ich prüfe etwas. = I check something.

Here, the something is jede Frist.

Also, Frist is a feminine noun, and for feminine nouns the form of jede is the same in nominative and accusative singular:

• nominative: jede Frist
• accusative: jede Frist

So the form does not change visibly here, but grammatically it is accusative.

Repeating the article is completely normal and usually sounds more natural here.

• die Leihfrist oder die Abholfrist

This clearly presents two parallel alternatives. In German, when two nouns are coordinated with oder, it is very common to repeat the article if each noun is being presented as its own full option.

You can sometimes omit articles in certain contexts, but here repeating die makes the structure clearer and more idiomatic.

The comma marks off the added phrase sei es die Leihfrist oder die Abholfrist, which comments on or specifies the general statement before it.

German punctuation often uses commas before inserted explanatory or supplementary structures like this. Here the part after the comma is not a completely independent main clause; it is an attached expression that elaborates on jede Frist.

So the comma helps show:

• main statement: Ich prüfe jede Frist
• added specification: sei es die Leihfrist oder die Abholfrist

Yes, it sounds somewhat formal, written, or carefully phrased.

In everyday speech, many speakers would choose simpler alternatives such as:

• Ich prüfe jede Frist, egal ob es die Leihfrist oder die Abholfrist ist.
• Ich prüfe jede Frist, ob das nun die Leihfrist oder die Abholfrist ist.

The original sentence is absolutely correct, but sei es ... oder ... has a slightly elevated tone. You are especially likely to see it in writing, presentations, formal explanations, or polished speech.

Yes. Some more everyday alternatives are:

• ..., egal ob es die Leihfrist oder die Abholfrist ist.
• ..., ob es nun die Leihfrist oder die Abholfrist ist.
• ..., ob das die Leihfrist oder die Abholfrist ist.

These are often easier for learners to produce.

However, the nuance is a little different:

• sei es ... oder ... = concise, elegant, somewhat formal
• egal ob ... = very common and conversational
• ob es ... ist = neutral and straightforward

Yes, both are compound nouns, which are very common in German.

They are built like this:

• Leihfrist = Leih-

  • Frist
  • leihen relates to lending/borrowing
  • Frist = deadline, period, time limit

• Abholfrist = Abhol-

  • Frist
  • abholen = to pick up, collect
  • Frist = deadline, period, time limit

In German compounds, the last part usually determines the grammatical gender and the basic category of the word. Since Frist is feminine, both compound nouns are also feminine:

• die Leihfrist
• die Abholfrist

Yes, that is possible, but it changes the style and emphasis.

Your original sentence:

• Ich prüfe jede Frist, sei es die Leihfrist oder die Abholfrist.

This is the most natural order if you first want to make the general statement and then add examples.

Fronting the phrase is possible:

• Sei es die Leihfrist oder die Abholfrist, ich prüfe jede Frist.

That sounds more rhetorical or literary. It puts stronger emphasis on the alternatives first.

So grammatically it can work, but for most neutral contexts, the original order is smoother.

Because the sentence is presenting alternatives, not a list that must all apply at once.

• oder = or
• und = and

Here the idea is: whatever kind of deadline it is, whether it is one kind or the other, I check it.

If you used und, it would sound like both nouns are being combined rather than presented as alternative examples, which is not the intended meaning of sei es ... oder ....

Not always. It often introduces alternatives, but it can also introduce examples more generally.

Common patterns include:

• sei es A oder B
• sei es wegen A, sei es wegen B
• sei es aus Interesse, sei es aus Pflichtgefühl

So sometimes you get oder, and sometimes the structure repeats sei es before each option.

For a learner, the most useful pattern to recognize first is:

• ..., sei es A oder B.