If a person has not had enough sleep, his actions will give him ___ during the day.

We often say that something is “as light as air”, but air is＿＿＿light. 

＿to my regret, I am unable to accept your warm invitation. 

— Look! Black clouds are gathering.— Yes. A heavy rain is ______  to come.

I shall certainly not tell him the news. ________, it will go to his ears sooner or later.