Read about linking words of contrast (however, although ...) here.
We use linking words to join ideas together when we're talking or writing. Sometimes we want to show that one thing happened because of another thing. We can use linking words like 'because' or 'since' or 'due to' to do this.
Words (or groups of words) that are followed by a clause
We can use these words at the beginning or in the middle of a sentence. They are used in front of a clause (a clause has at least a subject and a verb that agrees with the subject). They go before the reason. If they are at the beginning of the sentence, we put a comma in the middle to separate the clauses.
Because
- We cancelled the picnic because it was raining.
- Because it was raining, we cancelled the picnic.
- We cancelled the picnic as it was raining.
- As it was raining, we cancelled the picnic.
- We cancelled the picnic since it was raining.
- Since it was raining, we cancelled the picnic.
We can also use 'for' to mean 'because'. This is very literary and we don't really use it in spoken English. 'For' can only go in the middle of the two clauses. We often add a comma before it.
- We cancelled the picnic, for it was raining.
Words (or groups of words) that are followed by a noun
Because of + noun
- We cancelled the picnic because of the rain.
- Because of the rain, we cancelled the picnic.
- We cancelled the picnic due to the rain.
- Due to the rain, we cancelled the picnic.
- We cancelled the picnic owing to the rain.
- Owing to the rain, we cancelled the picnic.
*Some very traditional grammar books say that because 'due' is an adjective, we should only use it after a noun and the verb 'be'. So we should say 'the cancellation of the picnic was due to the rain' (instead of my example above), and we shouldn't use 'due to' at the beginning of a sentence. However, in modern English, it is fine to use 'due to' in the same way as 'owing to' and 'because of'.