Answer:
Most of Western Europe has a marine west coast climate, while most of Eastern Europe has a humid continental climate.
Step-by-step explanation:
Western Europe is generally a region dominated by lowlands. It is exposed to heavy influences from the ocean, with the Gulf Stream being the dominant ocean current that influences the climate. The ocean manages to make the climate in this part of Europe mild throughout the year, but also with high amounts of precipitation, thus it falls into the category of marine west coast climate.
Eastern Europe is located deeper into the continental mass, and even though it is also dominated by lowlands, it has a much more pronounced continental influence in its climate. The summer temperatures tend to get high, while the winter ones very low, but because there aren't natural barriers with Western Europe, the ocean manages to have an impact as well, bring in solid amounts of precipitation. The climate in this region is predominantly of humid continental type.