Final answer:
The word 'strong' is an adjective that describes the intensity of the stream.
Step-by-step explanation:
The word strong in the sentence "The stream was strong and their going slow" is an adjective. In this sentence, the word "strong" is describing the intensity or force of the stream. It provides more information about the stream and helps paint a clearer picture for the reader.
Learn more about Part of speech of the word 'strong' in a sentence