Final answer:
The subject is Spanish and the grade level is High School. To conjugate 'hablar' for 'Yo', use 'hablo'.
Step-by-step explanation:
The subject of this question is Spanish because it is asking to conjugate a verb in Spanish to match the subject of the sentence. The grade level is High School because this is a grammar topic commonly taught in high school Spanish courses.
To conjugate the verb 'hablar' in the present tense to match the subject 'Yo' (I), you would use 'hablo'. So the full sentence would be 'Yo hablo español muy bien' which translates to 'I speak Spanish very well'.
Learn more about Conjugating verbs in Spanish