Premise: "Motorcycles parked at a grill restaurant."
Hypothesis: "Hells angel' motorcycles parked at a restaurant for their gathering."
Do we know that the hypothesis entailed by the premise? A step-by-step solution is:
Not all motorcycles belong to the Hell's Angel'. And the motorcycles do not need to be there for a Hells Angels Gathering. Their motorcycles could be there because a few of them wanted to get dinner or something.
The final answer: it is not possible to tell.