QUESTION: Given the sentence "A woman in a red jacket is sitting on a cement block." is it true that "A woman sits."?

Let's solve it slowly: A woman is sitting wearing a red jacket on a block.
The answer is yes.

QUESTION: Premise: "The dog is holding a branch."
Hypothesis: "Swimming in the river."
Do we know that the hypothesis entailed by the premise?

Let's solve it slowly: A dog jumped into the river to fetch a branch that was floating by.
The answer is it is not possible to tell.

QUESTION: Given the sentence "Person canoes in lake." is it true that "A river with no people around."?

Let's solve it slowly:
A river is not the same as a lake. There can either be a person or no people.
The answer is no.