Questions about en
Q: Why is it J'en ai parlé and NOT J'ai parlé de cela?
There is a strong preference in French for pronouns that come before the verb.
Q: Why is it J'en ai besoin and NOT Je l'ai besoin?
Since the complete expression is avoir besoin de, you need to use the pronoun en.
Q: Why is it J'en ai vu trois and NOT J'en ai vus trois?
Never make agreement when using en before the verb.
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