Breakdown of No los dejó sentarse en la cancha.
no
no, not
en
in / on / at
sentarse
to sit down
los
them (masculine direct object)
Questions & Answers about No los dejó sentarse en la cancha.
Why are there two pronouns (los and se) if they refer to the same group of people?
los (them) is the direct object of the first verb, dejó—it tells us who he didn't let. se is the reflexive pronoun that belongs to the second verb, sentarse (to sit down). You need both because "he didn't let them" (No los dejó) and "to sit down" (sentarse) each require their own pronoun to be grammatically complete.
Why do we use the direct object los instead of the indirect object les here?
When using dejar (to let) or hacer (to make) + an infinitive, the person you are allowing or forcing is the direct object (los) as long as the second verb doesn't have a direct object of its own. Since sentarse (to sit down) is just an action that doesn't act on another noun (unlike eating an apple or reading a book), "them" is a direct object, so we use los.
Could I attach los to the infinitive to make No dejó sentárselos?