Only when I left home to go to college ___ how much my mother had done for me.

I failed in the examination last term and only then ____ the importance of studies. 

Only an hour ago ________ out why he was absent.

---- Your father is very strict with you.      ---- ____. He never lets off a single mistake of ours.

By the side of the teaching building of our school _____, which was completed in 2009.