Both the stomach and the mouth involve both chemical and mechanical ways of digestion.

1. The Mouth:
- Mechanical Digestion: The process of digestion begins in the mouth, where the teeth break down food into smaller pieces through chewing or mastication. This mechanical action increases the surface area of the food, making it easier for enzymes to act upon it later in the digestive process.
- Chemical Digestion: Saliva, which is produced by the salivary glands, contains an enzyme called amylase. Amylase begins the chemical breakdown of carbohydrates in the food, breaking them down into simpler sugars.

2. The Stomach:
- Mechanical Digestion: After food passes through the esophagus, it enters the stomach. The stomach muscles contract and relax, churning and mixing the food with gastric juices. This muscular action helps to break down the food into smaller particles and mix it with digestive enzymes and acids.
- Chemical Digestion: The stomach secretes gastric juices, including hydrochloric acid and enzymes such as pepsin. Hydrochloric acid helps to create an acidic environment that activates pepsin. Pepsin is responsible for breaking down proteins into smaller peptides.

3. The Esophagus:
- The esophagus is a muscular tube that connects the mouth to the stomach. It primarily serves as a conduit for food to pass from the mouth to the stomach and does not play a significant role in digestion. Therefore, it does not involve both chemical and mechanical ways of digestion.

In conclusion, both the stomach and the mouth involve both chemical and mechanical ways of digestion. The mouth mechanically breaks down food through chewing and chemically breaks down carbohydrates through the action of amylase in saliva. The stomach mechanically breaks down food through muscle contractions and chemically breaks down proteins with the help of gastric juices and enzymes.