This has nothing to do with modal verbs but with verbs' constructions: with or without a preposition to introduce the object.
- chercher quelque chose/quelqu'un (directly transitive = no preposition) = to look for, to search for (indirectly transitive = with a preposition).
That would call for an expression like "je vais chercher mon chien" where "aller" + "chercher" are interpreted together to mean "fetch", "get", "pick up". Je vais chercher mon fils après d'école = I am picking up my son after school. http://www.wordreference.com/fren/aller%20chercher
Usually, Kelly, however when the Feminine noun that the possessive relates to begins with a vowel sound the possessive defaults to the masculine Mon as in My Water is not Ma Eau not M'eau but defaulted to Mon Eau.. In this lesson's task the dog if its gender is male, or not known it's Mon chien but if we definitely know that it is a female dog (a ❤❤❤❤❤) it is Ma chienne.
Hi Amarmswj. These are possessives. Mon=My preceding a masculine noun. Ma=My preceding a feminine noun. Mes=My preceding a plural noun. Votre=Your preceding masc/fem noun when speaking to some one rather formally. Vos=Your preceding a plural noun when speaking to a group rather formally. Ton=Your preceding a masculine noun when speaking to someone dear to you or a child. Ta=Your preceding a feminine noun when speaking to someone dear to you or a child. Tes=Your preceding a plural noun when speaking to someone dear to you or a child. Notre=Our preceding a singular masc/fem noun and Nos=Our preceding a plural noun. Phew! My brain hurts, how's yours? :) JJ.