I went along thinking of nothing________, only looking at things around me.[ ]
David, there _____ a dictionary and some books on your desk. Please put them away.— OK, Mum. I’ll do it right away(马上).
China’s population is expected to increase to about 1.5 billion in 2040, _____ it will start to decline slowly.
Did he come back early last night? —- Yes. It was not yet eight o’clock _______ he arrived home.
The meeting was to_________ but the manager________ until twenty minutes later.