Word order is very important in German! There are separate rules for main and subordinate clauses.
The main clause can either have direct or indirect word order, depending on whether the sentence begins with the subject or not.
If the sentence begins with the subject, the word order is direct, meaning that the conjugated verb follows the subject. The first sentence below is an example of this.
However, if the sentence begins with an adverb denoting time, manner or place, or the object, the word order is inverted, i.e. the conjugated verb comes before the subject. The same goes for sentences that begin with a question word.
NB! In German, the conjugated verb always occupies the second position in a main clause.
EXAMPLES:
Meine Schwester arbeitet als Lehrerin.
My sister works as a teacher.
Gestern haben wir Tennis gespielt.
We played tennis yesterday.
Wann kommt der Bus?
When does the bus arrive?
When several adverbs are used in a sentence with direct word order, they are organized in the following order: time – manner – place.
EXAMPLE:
Ich fahre um acht Uhr (T) mit dem Bus (M) zur Schule (P).
I go to school with the bus at eight o’clock.
Main clauses can be combined with the help of coordinating conjunctions (aber, denn, oder, sondern and und). Because they join two equal main clauses, they do not invert the word order. The conjugated verb still occupies the second position.
EXAMPLE:
Ich bin früh aufgestanden und (ich) habe ein großes Frühstück gegessen.
I got up early and I had an abundant breakfast.
However, main clauses can also be combined with subordinate clauses (i.e. sentences that generally do not make sense on their own). Subordinating conjunctions (als, bevor, dass, nachdem, ob, obwohl, weil and wenn), which are used to form subordinate clauses, affect the word order. Notice that the conjugated verb is always in final position in a subordinate clause.
EXAMPLES:
Ich habe bemerkt, dass du heute sehr müde aussiehst.
I noticed that you look very tired today.
Ich bleibe heute zu Hause, weil ich mich erkältet habe.
I am staying home today, because I caught a cold.