After playing to much with tools like localepurge and bleachbit, I recently had the same problem.
A possible solution is:
dpkg -l | grep engb | awk '/^ii/ { print $2 }' > packages.txt
(this lists all your installed English language files)
apt-get install --reinstall `cat packages.txt`
(this should reinstall them)
On my system I have trouble with the repos (fiddled to much trying to save some space), so I can't reproduce my solution and redownload the files. But at least in theory it should work.
Tell me, if it worked.