Answer:
The mistake in each sentence is the conjugation of the verbs.
1.Yo nado
2. Ellos cantan.
3. Yo canto
Explanation:
1. Yo nado = verb in the first person of the singular is conjugated like nado, becasuse nadar is infinitive.
2. Ellos cantan = Verb in the third person plural form is conjugated like CANTAN, the way cantamos is for the first person in plural (nosotros cantamos).
3. Yo canto = Verb in the first person in singular is conjugated like canto. CANTAS is the conjugation for the second person singular (tú cantas).
