Only when he had done it ______ that he had made a mistake.
The truth, Sir, is that the old man____ across the street when my car hit him.
. ---Where will you start your work after graduation?---Mmm, it's not been decided yet. I ____ continue my study for a higher degree.
. I wrote to my parents once a week,____ I was too busy with my teaching work.
. However, at times this balance in nature is disturbed, ____ a number of possibly unforeseen effects.
.--- He has to finish the experiment today. He must be in the lab,____?---That s quite possible.