We must keep on learning if we want to keep up with the     of the changing times.

 The ___of North Korea and South Korea is getting worse and worse these days.

Here’s my card． Let’s keep in＿＿＿＿＿．

As a result of destroying the forest, a large ________ of desert ________ covered the land.

We live too far from the city to get a strong TV ________.