Tom,come here. You ______ on the phone.
There are________many students on the playground.I can hardly find Tom.
—Excuse me.what’s this for? —It’s a cleaner and it________to pick up dirt.
We believe scientists will________a way to solve the air pollution.
Could you________the restaurant and order sortie take-away food for me?I’m a little hungry.
—Attention,please.The plane has to be________because of the heavy rain. —Oh,bad luck!We have to wait now.