QUESTION: Premise: "Three asian people standing on a sidewalk with a street scene in the background."
Hypothesis: "Three asian people are sitting down inside eating food at a restaurant."
Do we know that the hypothesis entailed by the premise?

Let's solve it slowly: The three Asian people are either standing on a sidewalk or sitting down inside eating food at a restaurant.
The answer is no.

QUESTION: Given the sentence "Man with a mustache standing next to a woman in a white shirt watching fireworks." is it true that "A man is standing."?

Let's solve it slowly: If a man is standing next to a woman then we already know that he is standing.
The answer is yes.

QUESTION: Premise: "A jockey rides his brown horse as the horse gallops along the track."
Hypothesis: "The jockey is getting ready to race with the horse."
Do we know that the hypothesis entailed by the premise?

Let's solve it slowly:
A jockey rides his brown horse as the horse gallops along the track does not indicate that the jockey is getting ready to race with the horse.
The answer is it is not possible to tell.