Your body can hiccup, sneeze and yawn. Let's look at hiccups first.

Your diaphragm is a muscle under your lungs. It helps you breathe.

Sometimes your diaphragm jerks. That jerk is called a spasm, and you cannot stop it. It makes a quick "hic" sound.

What can start hiccups? Eating too much or too fast can. So can fizzy drinks. So can getting very excited.

Most people get hiccups sometimes. They go away by themselves in a few minutes.

Now for a sneeze. A sneeze is a sudden burst of air. It rushes out of your nose and mouth. It helps clear dust and dirt out of your nose.

A sneeze is a reflex. A reflex is something your body does on its own. You cannot decide when it happens.

Cover your nose and mouth with a tissue when you sneeze. No tissue? Sneeze into your elbow. Then wash your hands.

A yawn is when you open your mouth wide. You take a long, deep breath. Cats, dogs, birds and fish yawn too.

People tend to yawn most when they have just woken up or when they are tired. People often yawn when they are bored.

Yawns are catching. When you see someone yawn, you often yawn too. Are you yawning yet?

Words to know

• diaphragm: breathing muscle
• spasm: sudden jerk
• reflex: automatic action
• tissue: soft paper