The manager of the company told us that very little _________ was made of the waste material in the past.

Some countries are increasing their use of natural gas, and other forms of ______. 

You’d better put the papers and magazines into_____ bag.

I wished to make a round-the-world tour by plane but I hadn't enough money to pay for the ___.

Of the seven days in a week. Saturday is said to be the most popular _______ for a wedding in some countries.