Our attitude towards life is________makes the difference between our being happy or not.
When it comes to the human tendency to use the right hand much more often than the left hand, we seem to have __________ it from our animal ancestors, namely monkeys and chimpanzees.
Jim, I am sure __________ we met, we were at a rock concert, and since then we’ve known each other.
--- Ouch! You stepped on my toe! --- I’m sorry, I didn’t __________.
I wonder when it was __________ you came to realize __________ he said meant.
--- How come you know the accident so well? --- Well, because I was on the __________.