Several difficult geographical problems, I hope everyone will help me enthusiastically!

2 Heilongjiang-Jilin, Russia. Liaoning-Inner Mongolia, North Korea-Xinjiang, Russia-Kazakhstan, Kyrgyzstan, Tajikistan, Afghanistan, Pakistan, Tibet-Pakistan, India, Nepal, Bhutan, Myanmar, Yunnan-Myanmar, Laos, Vietnam and Guangxi-Vietnam.

3 Low density-Xinjiang Tibet high density-Henan Shenzhen Shanghai Guangdong Anhui Jiangsu Sichuan

Distribution characteristics-developed traffic, developed economy, along rivers or estuaries

This climate belongs to temperate continental climate. Rainfall is scarce, and dry climate can easily lead to land dryness, desertification, water shortage and insufficient soil fertility, which is not conducive to crop growth. We should plant more trees and grass, develop irrigated agriculture, use water rationally and raise people's awareness of environmental protection.

5 appears in the two solar terms of "ear seed" and "summer solstice". The rainfall is between 200 and 400 mm.