So absorbed_____in her work that she didn’t realize I was behind her.

Shall we go and ________ hello to the old man—Good idea! Let’s go.

Facts prove that the world’s economic development isnot a win-lose game but one in which all ______ be winners.

Not until the child fell asleep_______leave the room.

You needn’t call Tom. I ______ ten minutes ago and he ______ the invitation.