If I understand your question, because you have past participles above: choisi, fait, vu, envoyé.....you are referring to the agreement of past participles conjugated with avoir, or the passé composé, with preceding direct objects. Then the past participle agrees in number (singular/plural) and gender (masculine/feminine) with that preceding direct object.
That is the house that I have chosen = C'est la maison que j'ai choisie. (Note the past participle being singular and feminine just as "la maison" is, because "la maison" is the preceding direct object.
Here is the homework (the tasks) that he has done. = Voici les devoirs qu'il a faits. (masculine & plural)
Ce sont les jeunes filles que nous avons vues. These are the girls that we have seen. (feminine & plural)
Ce n'est pas le livre qu'ils ont envoyé. = That is not the book that they sent. (It may appear there is no agreement because "le livre" is masculine and singular.)
Please feel free to ask any questions. Was this what you were referring to in your post.
Since one can not "pretend" to imagine accents where they should be, if you tell me 2 things, I can provide the chart for you to make accent marks on the computer.
1. Do you have a MAC or PC.
2. Do you have Windows or not.
Sra (aka Mme)
P.S. Although you did not ask, past participles conjugated with être, agree in number and gender with the subject. (1)
Quand sont-ils sortis? = (When did they leave?)
Sa femme est née en Afrique. = (His wife was born in Africa.)
It is a bit trickier with Reflexive Verbs in that the reflexive pronoun *me, te, se, nous, vous, se) is not always a direct object. It ma be an indirect object, with or without a direct object expressed in the sentence. (2)
Ils se sont arrêtés court. = They stopped short.
Où sont les cravates qu'il s'est achetées? = Where are the ties he bought (for himself)?
Elle s'est brossée. = She brushed herself.
BUT: Elle s'est brossé les cheveux. = She brushwed her hair. (her hair is a following direct-object and the "s'" in this case is the indirect-object pronoun)
Nous nous serions écrit. = We would have written to each other (ourselves). (The direct-object "probably letters" is not stated and the reflexive pronoun is again an indirect-object pronoun.)
With the verb "parler" has no agreement because it takes an indirect object. (3) Nous nous sommes parlé. = We spoke (words, etc.) to each other.
Past participles can also be used as adjectives and must agree with the noun they modify. Les bijoux étaient cachés. = The jewels were hidden.
Je dis que le latin n'est pas une langue morte. = I say Latin is not a dead language.
Sra (aka Mme)