The correct sentence is: “They don’t go to school on Sundays.”
Explanation:
“They doesn’t go to school on Sundays”
Incorrect because “doesn’t” is used with singular subjects (e.g., “he,” “she,” “it”). The plural subject “they” requires “don’t.”
“They don’t goes to school on Sundays”
Incorrect because the verb “goes” is used with singular subjects when using present simple tense (e.g., “he goes”). For plural subjects like “they,” the base form “go” should be used after “don’t.”
“They don’t go to school on Sundays”
Correct because “don’t” (do not) is the negative auxiliary verb used with plural subjects, and the base form “go” is used with it.
“They not go to school on Sundays”
Incorrect because it lacks the auxiliary verb “do.” In English, negatives in the present tense require an auxiliary verb (e.g., “don’t” or “doesn’t”).