. I have taught hundreds of students,___________ having been working in their fields for years.

_________ is unknown to us all.

The parents seemed satisfied with the news __________ their son had been employed by a large company.

We have overlooked the fact __________ the children’s emotional development may be easily damaged.

In Mark’s speech, he made the point __________ far more people died from smoking than from taking drugs.

It is already well understood___________ causes the global warming.

_________he said at the meeting astonished everybody.

Obviously they didn’t see the significance of the plan. That’s __________the problem was.

Hearing his father was seriously ill, ______.

----Where did you meet him?
----It was in the hotel ______ he stayed ______ I met him.