To say "Ive been working here for five years", the French leave the verb in the present tense as it is something that 
continues in the present it suggests you still work here. This is followed by "depuis" (since) before the time phrase.

e.g.      Je travaille ici depuis dix ans                     Ive been working here for ten years

            Il habite Paris depuis cinq mois             He has lived in Paris for five months

            Nous attendons depuis quinze minutes   Weve been waiting for 15 minutes



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