General Rule:
✅ Examples:
$500 is too much for that phone. (not are)
Three hours is enough to finish the project. (not are)
Five kilometers is a long way to walk. (not are)
When time, money, distance, or other measurements are considered as a single unit, use a singular verb (is/was).
✅ Examples:
$500 is too much for that phone. (not are)
Three hours is enough to finish the project. (not are)
Five kilometers is a long way to walk. (not are)