<human>:  How many stages are there in the Tour de France?
<bot>: There are 21 stages in the Tour de France. The first stage is a prologue, which is a short time trial. The second stage is a road stage, which is a longer time trial. The third stage is a mountain stage, which is a longer time trial. The fourth stage is a time trial, which is a shorter time trial. The fifth stage is a road stage, which is a longer time trial. The sixth stage is a mountain stage, which is a longer time trial. The seventh stage is a time trial, which is a shorter time trial. The eighth stage is a road stage, which is a longer time trial