________is well known to everyone，I should say，is that a man becomes learned by asking questions

____the morning of the second day of the meeting, DrSmith read his paper

George returned after the war, only _______ that hiswife had left him.

He took pity on the people in theflooded-areas and ______ his clothes and quilts to them]

You left your umbrella.______. I’m becoming so forgetful these days.