When we talk about what someone needed to do in the past in Russian, we use the word "должен." This word means "must" or "should." It’s important to know how to use it correctly in different situations. Let’s go over some simple rules and examples.

Forms of "должен"

1. For a boy or man (masculine): "должен"

   • Example: Он должен был прийти. (He had to come.)

2. For a girl or woman (feminine): "должна"

   • Example: Она должна была прийти. (She had to come.)

3. For a child or an object (neuter): "должно"

   • Example: Оно должно было прийти. (It had to come.)

4. For more than one person (plural): "должны"

   • Example: Они должны были прийти. (They had to come.)

Using "должен" in Past Tense

To say "должен" in the past, we add a form of the verb "быть," which means "to be." Here’s the easy way to structure it:

• Subject + должен/должна/должно/должны + был/была/было/были + verb

Examples

• For Myself: Я должна была закончить проект. (I had to finish the project.)
• For General Statements: Это должно было быть сделано раньше. (This had to be done earlier.)

What Are Modal Verbs?

It’s useful to know what modal verbs mean:

• Necessity: "должен" shows you need to do something. It means you don't have much of a choice.
• Possibility: Another word, "можно," means you can do something or it’s okay.
• Permission: "можно" can also be used to ask for permission, giving you more options.

Practice Changing Sentences

Let’s change these sentences to the past tense using "должен":

1. Я должен пройти экзамен. (I must pass the exam.)
2. Ты должна купить продукты. (You must buy groceries.)
3. Мы должны закончить домашнее задание. (We must finish the homework.)

Answers:

1. Я должен был пройти экзамен. (I had to pass the exam.)
2. Ты должна была купить продукты. (You had to buy groceries.)
3. Мы должны были закончить домашнее задание. (We had to finish the homework.)

By learning these forms and their meanings, you can easily talk about what needed to be done in the past in Russian!