When your enemies hide and bullets can't get them, it's the perfect time to use grenades. Throw them towards the enemy and kill all soldiers by using as less ammo as possible.
Fortunately, the majority of people had never been and will never be in the combat. It's a nightmare no one should ever experience, but if you want to test some of known weapons you should play games. This game is about throwing grenades and cause maximum damage to your enemies, that hide in their comfortable shelters.