Adverbien.
They never change.

An adverb adds information about a verb, an adjective, or another adverb: when, where, how, how much. In German, an adverb never takes an ending. It does not matter where it stands in the sentence or what it describes: no case, no gender, no number ever touches it. (It can still be compared: schnell, schneller, am schnellsten, but that is the only way it changes at all.) That makes adverbs the easiest word class in German, and the perfect counterpart to adjectives, which change constantly.

No endings, ever

The previous article covered adjective endings: an adjective directly before a noun takes an ending that depends on the case, gender, and article of that noun. An adverb never does this, because an adverb never stands directly before a noun describing it. It describes a verb, an adjective, or another adverb instead, and none of those require an ending.

Sentence	Word	Job	Ending?
DerschnelleZug fährt nach Berlin.	schnelle	Adjective, describes der Zug	Yes, -e
DerZug fährt schnell.	schnell	Adverb, describes fährt	No

Same word, same meaning, two different jobs. The first schnell sits before Zug and has to agree with it, so it takes -e. The second schnell describes how the train goes, not the train itself, so it stays in its bare form.

Full breakdown of when and why adjectives take endings: Adjektive. How they describe nouns.

Same word, two jobs

Most German adjectives can also work as adverbs without changing their base form at all. The dictionary entry is the same word. Position tells you which job it is doing: directly before a noun, it is an adjective and needs an ending. After the verb, describing the verb, it is an adverb and stays untouched.

Word	As adjective (ending required)	As adverb (no ending)
schnell	derschnelleZug	Er läuft schnell.
gut	dieguteIdee	Das funktioniert gut.
laut	daslauteKind	Sie singt laut.
langsam	derlangsameBus	Wir fahren langsam.

Once a word is learned, there is nothing extra to memorize for its adverb form. The only thing to watch is position: before a noun, expect an ending; anywhere else describing an action or a quality, leave it alone.

What adverbs can describe

An adverb has three possible targets, and the target never changes its form either.

Adverb describes	Example	What it modifies
A verb	Er spricht langsam. (He speaks slowly.)	spricht: how he speaks
An adjective	Das ist sehr interessant. (That is very interesting.)	interessant: how interesting
Another adverb	Er spricht sehr langsam. (He speaks very slowly.)	langsam: how slowly

In all three cases, the adverb stays exactly as it is. sehr is always sehr, whether it intensifies an adjective or another adverb. Nothing about it ever changes.

Adverbs and the verb-second rule

German main clauses always put the finite verb in position 2. The subject usually fills position 1, but it does not have to. Any single element can open the sentence, including an adverb. When an adverb takes position 1, the subject and verb swap places. The verb stays in position 2, and the subject moves right behind it. This is called inversion.

Position 1	Verb (pos. 2)	Subject	Rest
Heute	arbeite	ich	nicht.
Morgen	fahren	wir	nach Berlin.
Leider	kann	ich	nicht kommen.

Nothing about the adverb itself changes here either. Only the word order around it shifts, and only because position 2 is reserved for the verb, no matter what.

This swap in detail, with one adverb at a time: dann. Then. What comes next. and trotzdem. Nevertheless. The verb stays. Why position 2 belongs to the verb in the first place: Verben. They frame the sentence.

TeKaMoLo: ordering several adverbs together

Sentences often carry more than one piece of "when, why, how, where" information at once. Some of these are single adverbs, like morgen or heute. Others are short phrases built with a preposition, like wegen der Prüfung or mit dem Bus. Both types answer the same kind of question and slot into the sentence the same way, so German orders them together using one rule, known by the acronym TeKaMoLo: temporal (when), kausal (why), modal (how), lokal (where). It is a strong tendency rather than an absolute law, but it is the right place to start.

Te (when)	Ka (why)	Mo (how)	Lo (where)
morgen	wegen der Prüfung	mit dem Bus	zur Uni

Ich fahre morgen wegen der Prüfung mit dem Bus zur Uni. (I'm going to university tomorrow by bus because of the exam.)

Only morgen is an adverb here. wegen der Prüfung, mit dem Bus, and zur Uni are prepositional phrases doing an adverb's job: each one answers when, why, how, or where, just like a single adverb would. TeKaMoLo is about that job, not about the word class. Whatever fills the "when" slot goes first, whatever fills "why" goes next, and so on, regardless of whether it is one word or several. Notice that wegen and mit / zu keep their usual case colors here too: the color always tracks the case a preposition takes, no matter what role the phrase plays in the sentence.

Read it as a chain of questions answered in order: when am I going? Tomorrow. Why? Because of the exam. How? By bus. Where to? To university. Most sentences only use two or three of these slots, but when more pile up, this is the order they fall into.