因为 often pairs with 所以 (therefore): 因为...所以... is the standard 'because...therefore...' pattern. In English we'd only use one, but Chinese uses both together.
mistakes
Don't combine 因为 with English-style logic. In Chinese, you say 因为A，所以B — never 因为A，但是B. The 'because...but...' pattern doesn't work in Chinese.
usage
因为 can start a sentence or appear mid-sentence. When it starts a sentence, the 所以 clause usually follows after a comma.
