Conjunctions are joining words. They link two clauses to make them into one. Some of them affect the word order:
coordinating conjunctions are easy as they do not change the word order
subordinating conjunctions send the verb to the end of the clause
Coordinating conjunctions
The following words are the coordinating conjunctions. They do not change the word order.
aber - but
denn - as, since (in the sense of because)
oder - or
sondern - but (in a contradiction)
und - and
They are used to join two clauses. If the clauses are not joined together by a coordinating conjunction, both clauses will still make perfect sense on their own.
aber
Ich esse viel Obst, aber ich hasse Bananen. - I eat lots of fruit, but I hate bananas.
denn
Sie sind ins Konzert gegangen, denn sie wollten ihre Lieblingsband sehen. - They went to the concert, because they wanted to see their favourite band.
oder
Wir sehen abends fern oder wir lesen. - We watch TV in the evening or we read.
sondern
Ich werde nicht Spanisch studieren, sondern Deutsch. - I won't study Spanish, but German.
und
Ich bin sehr sportlich und ich trainiere viermal die Woche. - I am very sporty and I train four times a week.
Question
Link the two clauses with the conjunction. What do they mean?
Sie trinkt keinen Kaffee. Sie trinkt Tee. (sondern)
Sie möchten studieren. Sie wollen Geld verdienen. (aber)
Sie trinkt keinen Kaffee, sondern sie trinkt Tee. - She does not drink coffee, but she does drink tea.
Sie möchten studieren, aber sie wollen Geld verdienen. - They want to study, but they also want to earn some money.