Bill (imparfait|corrigezmoi)

[feral meadow]

Please be patient

Our volunteers look into many questions every day; sometimes it takes them a little while to answer.

Pro tip: you can rename the thread title with `.tr <thread name>`

Make it descriptive, including relevant context, but also to the point. This way you improve your chances of getting a more relevant and specific answer.

[vague gull]

Let's use another verb for the sake of the example:
je parle à Thomas (I'm speaking to Thomas)
"parler" uses "à" before the object. This is an indirect object. If you want to replace Thomas by a pronoun, you have to use the appropriate indirect object, which is "lui"
je lui parle (I'm speaking to him)
as you can see, "lui" goes before the verb, as all object pronouns do.

This is the same exact phenomenon in your sentence
faire plaisir [à quelqu'un] => lui faire plaisir (lui is referring to the person that's pleased)

[uneven palm]

Recent past is aller + infinitive verb. So not a legit tense but a verbal structure. A tense would simply have just the verb conjugated.
Besides, object pronouns go right before the verb they relate to.

[shrewd drum]

Only the auxiliaries, avoir and être attract object pronouns to them: all other auxiliary and moda verbs leave them on the main verb.

avoir and être require a past participle and not an infinitive, and object pronouns cannot stand right before a past participle ("le trouvé" is not grammatical un any context)

Thus:
Je t'ai vu
Je vais te voir

Ça lui a fait plaisir
Ça va lui faire plaisir