A ring is a piece of jewelry that you wear on your finger. Rings can be made out of almost anything, but are usually made from some kind of metal with some kind of stone set into them. The lady in the picture has three rings on her hand. Plain rings are generally worn by a married couple after their wedding.
A tiara is a piece of jewelry that you wear on your head. It is much smaller than a hat and is usually made from metal with gemstones attached. Brides often wear tiaras when they get married.
Plastic tiaras like the one in the picture are very popular with children who like to play at being princesses.
Tis forToggle (joint)
A watch is something you can use to tell the time on. Watches are small and usually have a strap on, so you can wear them around your wrist. Large watches that you hang on the wall are called clocks.
It is useful to know the time, so you know when to go to school, or have dinner, or watch your favorite TV show.