Vatican Website translation:
27. It is to be stressed that whenever rites, according to their specific nature, make provision for communal celebration involving the presence and active participation of the faithful, this way of celebrating them is to be preferred, so far as possible, to a celebration that is individual and quasi-private.
This applies with especial force to the celebration of Mass and the administration of the sacraments, even though every Mass has of itself a public and social nature.
27. Quoties ritus, iuxta propriam cuiusque naturam, secum ferunt celebrationem communem, cum frequentia et actuosa participatione fidelium, inculcetur hanc, in quantum fieri potest, esse praeferendam celebrationi eorundem singulari et quasi privatae.
Quod valet praesertim pro Missae celebratione, salva semper natura publica et sociali cuiusvis Missae, et pro Sacramentorum administratione.
Slavishly literal translation:
27. Whenever rites, according to nature proper to them, carry with themselves a communal [form of] celebration, with the presence and active participation of the faithful, it is to be stressed that, insofar as it can be done, this [form of] celebration is to be preferred to that which is individual and as-it-were private.
Which applies especially to the celebration of Mass (save the always public and social nature of whatever Mass) and to the administration of the Sacraments.
Article 27 makes even more explicit the principle announced in art. 26 that the liturgical form of celebration should embody and express the hierarchical and communitarian nature of the Church and its liturgy. Pray Tell readers may wish to continue the discussion begun at art. 26 about the practical consequences of taking this principle seriously in reforming/restoring/renewal the liturgy.