If the exhaust valve of a four-stroke cycle engine is closed and the intake valve is just closed, what stroke is the piston on?

When the exhaust valve of a four-stroke cycle engine is closed and the intake valve has just closed, the piston is in the compression stroke. During this phase of the engine cycle, the piston moves upward in the cylinder while both valves are closed. As the piston ascends, it compresses the air-fuel mixture that was drawn in during the intake stroke. This compression increases the temperature and pressure of the mixture, preparing it for ignition.

In a four-stroke cycle, the sequence of strokes is intake, compression, power, and exhaust. The intake stroke occurs first when the intake valve is open and the piston moves down to draw in the air-fuel mixture. Once that stroke is complete and the piston moves back up, the intake valve closes to seal the mixture in, marking the beginning of the compression stroke. This preparation is crucial for efficient combustion during the subsequent power stroke.