Reporting Commands in the Past
When you quote a command or an instruction directly, you usually use the imperative mood ("Drink more water!"). However, when you report that someone gave a command in the past, the grammar must shift.
If the reporting verb is in the past tense—such as mandar (to order) or aconselhar (to advise)—the verb from the original command shifts into the imperfect subjunctive.
The Imperfect Subjunctive
You can recognize the imperfect subjunctive by its characteristic double-s. It is formed using the third-person plural of the simple past as a base, taking these endings: -sse, -sses, -sse, -ssemos, and -ssem.
When reporting advice for the nós (we) form, pay special attention to the written accent. Because the stress falls on the antepenultimate syllable, verbs get an acute or circumflex accent on the vowel right before the ending (like -ássemos, -êssemos, or -íssemos).
Reporting Dietary Advice
You will use this grammar frequently when relaying lifestyle changes prescribed by a health professional. Verbs like evitar (to avoid), substituir (to replace), and mastigar (to chew) are common when discussing adjustments to your intake of calories and carbohydrates.