Meaning: The sentence describes a train moving at a high speed.
Choice of Words: Train is a type of vehicle that runs on a track. Goes is the present tense of go, which means to move from one place to another. Fast means moving at a high speed.
Alternative Expressions
The train is speeding along.
Meaning: This sentence also tells us that the train is moving at a high speed.
Choice of Words: The word "speeding" means to move at a high speed. "Along" means in a forward direction.
The train is racing down the tracks.
Meaning: This sentence tells us that the train is moving very fast down the tracks.
Choice of Words: The word "racing" means to move very fast. "Down" means in a downward direction. "Tracks" are the metal rails that the train runs on.