Vitamin C helps our bodies make a special chemical, which __________ affects our brains, making us feel happy.
.Many scientists believe that now we can study the behavior of a three-year-old child to see ____ they will grow up to be criminals.
.One advantage of eating a balanced breakfast is _____ it can keep you energetic throughout the day.
._____ you have a complaint to make, do something about it right away. The longer you wait, the harder it will be to get your complaint resolved.
.Mary had to work at evenings and weekends. Only in this way _____ complete the reports by the deadline.
.This city, _____ lies in the northeast, was the country’s busiest port from 1648 to 1950.