Of course, your answers are night, short, cold, and bases. Bases are the opposite of acids; they taste bitter and they feel very slippery and soapy. Bases are great cleaners and they brush decay away. Some bases are found in cleaning products such as car washing soap. Some bases are strong and dangerous. Bases can eat through grease, hair, and other gunk. Also bases are the reason toothpaste is so bubbly in your mouth.