The two companies decided to （ ） on a project concerning animal cloning.

The demand made by the workers is that their salaries （ ） to cover the increased cost of living.

Yon don’t have the right to blame me _____ being late， for I was busy typing your business invitations.

These university students are looking for a cheap hotel （ ）.

He （ ） by his sister at that moment.

There are many fashion shops and expensive restaurants on （ ） sides of the street.

It is essential that all these figures （ ） twice.

Little （ ） he knew about classical music, he pretended to be an expert on it.

No one except two servants （ ） late for the dinner.

My mother asked me where _____ the key.

We mention the importance of giving up smoking once and again, but hardly ______ it.

_____ with the developed countries, some African countries are left far behind in terms of people’s living standards.