comb怎么描述例如：wallet——it is not very big .We can put money in it那skateboard\watch呢,该如何描述,求救了,答对多给分,不过我很急,求救了SOS

it is made of wood or plastic, we can use it to comb our hair

comb----the little tool,you use it to tidy up you hair.
skateboard----it is on the ground or sometimes has wheels.you usually use it to make yourself flow forward on ground,for fun often.
watch---you often wear it on your wrist.you use it to show the time.