You are allergic to something if your body has a bad reaction to it. Allergic reactions can include getting a rash, sneezing, getting watery eyes or having difficulty breathing.
People are often allergic to dogs or cats, pollen or insect stings.
A bandage is a long, thin strip of fabric that you wrap around a part of your body that is hurt. You often see people who have a sprained ankle with a bandage wrapped around it.
A black eye is an injury that looks worse than it really is. A black eye, or shiner, can be caused by any damage near the eye or eyebrow. Even a small bump or knock can cause a spectacular black eye.
Your eyes are bloodshot if you can clearly see the blood vessels in them. You get bloodshot eyes when you are very tired, dehydrated, have conjunctivitis, or if your eyes have been damaged by something.
When you fall and hurt yourself or hit yourself hard on something else, you often get a dark purple or blue bruise. A bruise happens when the blood vessels under your skin get broken and you bleed under your skin. Bruises can take several days to go away.
A cramp is a pain in one of your muscles that often happens after exercise, or are caused by low salts in your blood. Cramps can hit suddenly and can be extremely painful. The person in the picture has a cramp in their leg.
Dandruff is when your head under your hair loses little white flakes of skin and they get caught in your hair or fall onto your shoulders. Dandruff can be itchy like in the picture, or just not be nice to look at.
You can buy special shampoo to get rid of dandruff.
A dentist is someone who looks after other people's teeth. They clean your teeth properly, and fix up holes in people's teeth. They can also make your teeth look better by straightening or whitening them. Sometimes going to see the dentist can be painful or scarey, so if you don't want a dentist trip to be bad, you should look after your teeth and brush them every day.