Eye gaze

When a person looks directly into your eyes when having a conversion, it indicates that they are interested and paying attention. However, prolonged eye contact can feel threatening. On the other hand, breaking eye contact and frequently looking away may indicate that the person is distracted, uncomfortable, or trying to conceal his or her real feelings.

Blinking
Blinking is natural, but you should also pay attention to whether a person is blinking too much or too little. People often blink more rapidly when they are feeling distressed or uncomfortable. Infrequent blinking may indicate that a person is intentionally trying to control his or her eye movements. For example, a poker player might blink less frequently because he is purposely trying to appear unexcited about the hand he was dealt.

Pupil size

One of the most subtle cues that eyes provide is through the size of the pupils. While light levels in the environment control pupil dilation, sometimes emotions can also cause small changes in pupil size. For example, you may have heard the phase "bedroom eyes" used to describe the look someone gives when they are attracted to another person.

Mouth expressions and movements can also be essential in reading body language. For example, chewing on the bottom lip may indicate that the individual is experiencing worry, fear, or insecurity.

Covering the mouth may be an effort to be polite if the person is yawning or coughing, but it may also be an attempt to cover up a frown of disapproval. Smiling is perhaps one of the greatest body language signals, but smiles can also be interpreted in many ways. A smile may be genuine, or it may be used to express false happiness, sarcasm, or even cynicism.

When evaluating body language, pay attention to the following mouth and lip signals:

Pursed lips

Pursed lips might be an indicator of distaste, disapproval, or distrust.

Lip biting

People sometimes bite their lips when they are worried, anxious, or stressed.

Covering the mouth

When people want to hide an emotional reaction, they might cover their mouths in order to avoid displaying a smile or smirk.