------ What made you so sad?------ ______ my wallet.
You can take the rest of the pie with you. ________, I wish you would, since I’m on a diet.
With the word “ PM2.5” ________ appearing in media reports, people pay greater attention to it and seek health tips for smoggy days.
He is talking so much about America as if he _____ there.
---How about going for a walk? --- ________ great. Let’s get going.
The teacher demanded that the exam _____ before eleven.