Final answer:
The correct form of the verb aprender to fill in the blank is aprendas.
Step-by-step explanation:
The correct form of the verb aprender to fill in the blank in the sentence 'Te aconsejo que ______ a hablar español' is aprendas. This is because the sentence is giving advice or a suggestion, and the subjunctive form of the verb is used in this context. The subject of the sentence is 'Te' which means 'you' in Spanish. So, the correct form is 'aprendas' which means 'you learn' in English.
Learn more about Verb conjugation in Spanish