We’ve all faked an emotion at one point or another to make the social situation we’re in a little bit more comfortable- laughing at a joke we don’t find particularly funny, smiling at someone you don’t like in greeting- yet some emotions (particularly fear and sadness) are more difficult to imitate. An article in Popular Science explains that it’s because these emotions are usually based on an internal struggle that results in a complex facial reaction. Wanting to cry, but at the same time, wanting to control your emotions can lead to a quivering lip. The stress of fear can be combined with other feelings, making it harder to pretend. However, they say your best bet when pretending to feel a certain way is to blend in with the emotions of everyone around you. People naturally project their own feelings onto others, so if you’re with a group of happy people, they’re more likely to take your fake smile at face value than notice you’re not genuinely grinning. Or, if all else fails, use physical cues that will draw attention away from your face. Think putting your head in your hands, or throwing up your arms in surprise.