Explanation
1. For and since
Error Source.
For and Since pose problems for German learners of English because the two words are translated in German with one word, Seit; a word that resembles the English word Since and means since but not in all contexts.
Unlike in German there is a difference between SINCE (a specific time) and FOR (a space of time.)
Example:
Er lebt seit drei Jahren in Deutschland. (Space of time) = FOR
Er lebt seit 2010 in Deutschland. (Specific time) = SINCE
Both prepositions are Seit but the English cannot translate all the two with SINCE.
Three years is a length of time so the English translate:
seit drei Jahren with for three years.
But when Seit is used in the sense of a date, a year, a day then since is used.
So:
seit 2010 means since 2010.
NB: Since and For are strong indicators for the use of the Present perfect continuous. He has been working since 2010
H e has been working for three years.
For - a period of time, a space of time, a length of time.
for three hours
for a week
for five years I have been working for two hours.
for a long time
for a number of days
for a number of hours
for a couple of years etc.
Since- a specific time, the time when the action began.
Since 2010
since Monday
since last year I have been living in Germany since 1990.
since Easter
since 1945
since my childhood
since this morning
since 12 o'clock
So far the difference is clear but there is another little trick to quickly know when to use since or for.
When it is possible to use the German word lang instead of the word seit, then use For.
seit 10 Jahren- 10 Jahren lang - f or 10 years
seit 5 Minuten- 5 Minuten lang - for 5 minutes
seit drei Wochen- drei Wochen lang- for three weeks
seit zwei Tage- zwei Tage lang- for two days
seit drei Stunden- drei Stunde lang- for three hours
BUT
seit 1990 1990 lang is bad German since 1990
seit heute Morgen since today morning
seit 13 Uhr- since one o'clock.