It's no secret to us, but he alone is in the dark. It means ____.
. Don’t promise anything _____ you are one hundred percent sure.
You _____ tell him. He is fully aware of the danger.
_____ his ability of speech, he has made use of each chance.
People pay ______as to the content of your speech.
____ I paid a visit to this scenic spot, I was deeply attracted by its beauty.