Simplify the following text for a Grade 10 native English-speaking person.
Original: The nation 's international economy was based on the wool trade , in which the produce of the sheepwalks of northern England was exported to the textile cities of Flanders , where it was worked into cloth .
Simplified: The nation 's international economy was based on the wool trade , where wool from northern England was sold to the textile merchants of Flanders to make into cloth .