They are used in many places, and the technology is constantly improving.
In the process of production their construction was improved constantly.
By constantly improving how we develop and grow our people.
They are made using a manufacturing process that has been constantly improving for more than four decades.
Its literacy rate was low until the early 1980s, but has since improved constantly and is currently about 75%.
"We expected that life in all its aspects would constantly improve," he writes.
Toyota has high levels of management presence on the production line whose role is to 'know' and to constantly improve.
Since the mid-19th century, living accommodation has been constantly improved to meet residents' needs.
Training for learner drivers is also constantly improving, and countries are learning a great deal from each other.
Most of those are in still in development, being improved and changed constantly.