Final answer:
The adverbs in the given sentence are 'yesterday', 'somewhat', and 'foolishly', which modify the verb in terms of time, degree, and manner, respectively.
Step-by-step explanation:
In the given sentences, the adverbs are words that modify verbs, adjectives, or other adverbs by indicating time, manner, place, degree, etc. The adverbs in the sentence "Yesterday Kenny injured himself somewhat as he foolishly attempted to carry a box that was far too heavy" are 'yesterday', 'somewhat', and 'foolishly'. 'Yesterday' is an adverb of time, describing when the injury occurred. 'Somewhat' modifies the extent of the injury. 'Foolishly' is an adverb of manner, describing how Kenny attempted to carry the box.