Examples of things having two sides are:
1. Wind can help people generate electricity and play an important role in people's production and life, but wind can also cause natural disasters. Disasters harm people;
2. Nuclear energy can benefit mankind, such as generating electricity, but nuclear energy used in war will harm mankind;
< p> 3. Electric energy benefits mankind, such as lighting, but improper use can cause danger;
4. Water can irrigate crops. Human beings cannot live without water in their daily lives, but water The accumulation of floods will harm mankind;
5. Cars can facilitate people's travel, but the exhaust gas produced by cars will pollute the environment.