en_tn_lite_do_not_use/rom/03/19.md

whatever the law says, it speaks to

Paul speaks of the law here as if it were alive and had its own voice. Alternate translation: "everything that the law says people should do is for" or "all the commands that Moses wrote in the law are for" (See: rc://en/ta/man/translate/figs-personification)

the ones who are under the law

"those who must obey the law"

in order that every mouth may be shut

Here "mouth" is a synecdoche that means the words people speak. You can translate this in an active form. Alternate translation: "so that no people will be able to say anything valid to defend themselves" (See: rc://en/ta/man/translate/figs-synecdoche and rc://en/ta/man/translate/figs-activepassive)

the whole world held accountable to God

Here "world" is a synecdoche that represents all the people who live in the world. Alternate translation: "that God can declare everyone in the world guilty" (See: rc://en/ta/man/translate/figs-synecdoche)