Action must be taken to prevent that factory from ______ heavy smoke into the air.
| A．giving off | B．putting away | C．escaping from | D．dealing with |
I remember _____ word he said that day.
| A．all | B．both | C．each | D．every |
One of the students hasn't prepared _____ lessons very well.
| A．one's | B．ones | C．their | D．his |
His attitude to us is _____ of a comrade.
| A．one | B．it | C．that | D．those |
He was ill. _____ is why he didn't attend the meeting.
| A．This | B．It | C．There | D．That |
Will he come back to school tomorrow? I hope _____.
| A．that | B．this | C．so | D．it |