Depreciates means the country can now afford less goods and services on the international market.
Understand this well:
If a country's currency depreciates, the country's money is worth relatively less. You need more of the country's currency to exchange with foreign money.
That means other countries are better off when compared with the country in question.
Import prices are foreign prices, you are buying from other countries. If your money has lost value, you will need to pay more for the goods. Your purchasing power has decreased, meaning that of foreigners have increased. They can buy more of your goods and services with the same money as they were using before. That's why export prices fall, because their purchasing power increases.
If it's still confusing, lemme know...