One should keep ________ promise.
It is thought that one billion people I the world, ______is half the word’s workers, earn their living by farming.
—Hold the ladder for me! —That’s______
I think I was at school,______I was staying with a friend during the vacation when I heard the news.
There were two boys in the lab,______did the experiment successfully.
After the new technique was introduced the factory produced cars in 1994 as the year before.