Doctrina bona discipulis utilis est.

Good teaching is useful to the students.

Breakdown of Doctrina bona discipulis utilis est.

• esse: to be
• discipulus: the student
• utilis: useful
• bonus: good

Questions & Answers about Doctrina bona discipulis utilis est.

What is each word doing in the sentence?

Here is the grammatical role of each word:

• doctrina — the subject; nominative singular feminine
• bona — an adjective modifying doctrina; nominative singular feminine
• discipulis — dative plural; for the students or to the students
• utilis — a predicate adjective with est; it describes doctrina
• est — is

So the basic structure is:

[subject] + [adjective modifying subject] + [dative] + [predicate adjective] + [verb]

In very plain grammatical English: Good teaching is useful to the students.

Why does bona end in -a?

Because bona agrees with doctrina.

Doctrina is:

• feminine
• singular
• nominative

So the adjective modifying it must also be:

• feminine
• singular
• nominative

The adjective is bonus, bona, bonum = good.
Its feminine nominative singular form is bona.

So:

• doctrina bona = good teaching / good instruction