Final answer:
The sentence is not capitalized correctly. Proper nouns should be capitalized, while general terms should not, unless they are at the beginning of a sentence.
Step-by-step explanation:
No, the sentence is not capitalized correctly. In English, proper nouns, such as names of specific places or things, should be capitalized. However, general terms or concepts, such as 'spring' in this case, should not be capitalized unless they are at the beginning of a sentence. Therefore, the correct capitalization for the sentence would be: 'Since the geese are flying north, it must be a sign that spring is on the way.' This way, only 'Since' and 'Spring' are capitalized.