It is thought that one billion people I the world,  _____is half the word’s workers, earn their living by farming.

 I lost my way in complete darkness and, _____matters worse, it began to rain.

We will see you again next Saturday. ______, you must rest as much as possible and take good care of yourself．

She has worked at the bank for many years，nine ______.

These animals are all used to their environment,______, they have learned how to live successfully in their habitat．