После урока учительница положила указку на стол.

Because после means after and it requires the genitive case.

• урок = lesson
• genitive singular of урок = урока

So:

• после урока = after the lesson / after class

This is a very common pattern in Russian:

• после работы = after work
• после школы = after school
• после обеда = after lunch

In this sentence, урок most naturally means lesson or class period.

So после урока can be understood as:

• after the lesson
• after class

The best English translation depends on context. In a school setting, both are very natural.

Учительница specifically means a female teacher.

Compare:

• учитель = teacher, male teacher, or sometimes teacher in a general sense
• учительница = female teacher

Since the subject is feminine, the past-tense verb is also feminine:

• учительница положила

If the subject were masculine, it would be:

• учитель положил

So this sentence clearly tells you the teacher is female.

Положила is the past tense, feminine singular form of положить.

Breakdown:

• положить = to put, to place
• положил = he put
• положила = she put
• положили = they put

Russian past tense agrees with gender and number in the singular:

• masculine: -л
• feminine: -ла
• neuter: -ло
• plural: -ли

So because учительница is feminine, you get положила.

Because положила is perfective, and it presents the action as a completed whole: she put the pointer down.

In this sentence, we are talking about one finished action after the lesson, so perfective is natural.

Compare:

• положила = she put it down / she placed it
• клала = she was putting it down / she used to put it down / she put it down repeatedly or with focus on the process

The basic aspect pair is:

• класть = imperfective
• положить = perfective

So this sentence uses the perfective form because it describes a single completed event.

Because it is the direct object of the verb, so it is in the accusative case.

• dictionary form: указка
• accusative singular: указку

For many feminine nouns ending in -а, the accusative singular changes -а to -у:

• книга → книгу
• лампа → лампу
• указка → указку

Here, what did the teacher put?
Answer: указку.

Указка means a pointer or teaching pointer—the stick a teacher might use to point at a board, map, or screen.

It is a fairly school-specific word. In older or more traditional classroom imagery, it is especially common.

Because Russian uses different cases after на depending on whether you mean:

• movement onto/to a surface → accusative
• location on a surface → prepositional

Here the teacher put the pointer onto the table, so there is movement toward the surface:

• на стол = onto the table

Compare:

• Учительница положила указку на стол. = The teacher put the pointer on the table.
• Указка лежит на столе. = The pointer is lying on the table.

So:

• на стол = destination
• на столе = location

Yes, Russian word order is flexible.

This sentence has a very natural, neutral order:

• После урока — time
• учительница — subject
• положила — verb
• указку — object
• на стол — destination

But other orders are possible, depending on emphasis:

• Учительница после урока положила указку на стол.
• Указку учительница положила на стол после урока.

These all mean roughly the same thing, but the focus shifts a little. Russian often puts old or known information earlier and new or emphasized information later.

Because Russian has no articles.

English says:

• the teacher
• a pointer
• the table

Russian usually just uses the noun without an article:

• учительница
• указка / указку
• стол

Whether something means a or the is understood from context. In this sentence, English normally uses the because the situation sounds specific, but Russian does not need to mark that.

A natural stress pattern is:

По́сле уро́ка учи́тельница положи́ла ука́зку на стол.

Useful word stress:

• по́сле
• уро́ка
• учи́тельница
• положи́ла
• ука́зку
• стол

Stress is important in Russian because it is not always predictable, so it is worth learning words together with their stress.