Final Answer:
The verb in the sentence "Hard work on slow curved balls strengthened this skills" is "strengthened," and its subject is "hard work."
Step-by-step explanation:
In the given sentence, "strengthened" is the verb that denotes the action of making something stronger. The subject of this action, the one performing the hard work, is "hard work."
"Hard work" functions as a singular noun, and the verb "strengthened" agrees with it in the past tense. The sentence suggests that engaging in hard work, particularly on slow curved balls, resulted in the enhancement or reinforcement of a certain set of skills. The subject and verb relationship is vital for constructing clear and grammatically correct sentences, ensuring that the action aligns with the appropriate entity.
Understanding the connection between the subject and verb is essential in conveying the intended meaning of a sentence. In this case, it emphasizes the cause-and-effect relationship between diligent effort (hard work) and the positive outcome of skill improvement.