אחרי שאני מתקלחת, אני שמה משחת שיניים על מברשת השיניים.

Because the speaker is female.

In Hebrew, verbs in the present tense agree with the subject’s gender and number. So:

• אני מתקלחת = I shower / I am showering (said by a woman)
• אני שמה = I put / I am putting (said by a woman)

If a man were speaking, it would be:

• אחרי שאני מתקלח, אני שם משחת שיניים על מברשת השיניים.

Notice:

• מתקלחת → feminine
• מתקלח → masculine
• שמה → feminine
• שם → masculine

Hebrew often uses the present tense to describe habitual actions or a routine, where English may use the simple present too.

So this sentence is describing a regular sequence of actions:

• אחרי שאני מתקלחת = after I shower
• אני שמה... = I put...

Even though English sometimes feels more like a “general present,” Hebrew still uses present-tense verb forms here.

This is very natural for describing everyday habits.

שאני is made of:

• ש = that / when / which (a very common connector)
• אני = I

So אחרי שאני מתקלחת literally feels like:

• after that I shower
• more naturally: after I shower

In Hebrew, after words like אחרי (after), it is very common to introduce a whole clause with ש־.

So:

• אחרי המקלחת = after the shower
• אחרי שאני מתקלחת = after I shower / after I am showering

Usually, no—not in normal modern Hebrew.

In the present tense, Hebrew verbs usually do not clearly show person by themselves. For example:

• מתקלחת only tells you feminine singular
• it does not tell you whether it means I, you, or she

So אני is needed for clarity:

• אני מתקלחת = I shower
• את מתקלחת = you (feminine) shower
• היא מתקלחת = she showers

That is why שאני is important here.

מתקלחת is the feminine singular present form of להתקלח, meaning to shower or sometimes to bathe.

The מת־ beginning is part of the verb pattern. This verb is in the התפעל pattern, which often has a reflexive or self-directed sense.

So:

• להתקלח = to shower / to wash oneself
• אני מתקלחת = I shower / I am showering (female speaker)

You do not need to analyze the pattern every time, but it helps to know that מת־ is a normal present-tense shape for many התפעל verbs.

Because the speaker is female, so the verb must be feminine singular.

The verb is לשים = to put.

Present tense forms:

• אני שם = I put (male speaker)
• אני שמה = I put (female speaker)

A very common learner confusion is that שמה can also look like the word meaning there in unpointed Hebrew spelling. But they are pronounced differently:

• שמה = she puts / I put (feminine), pronounced roughly sama
• שמה = there, pronounced roughly shama

Context tells you which one is meant.

That is just how Hebrew says toothpaste.

It is a construct phrase:

• משחה = paste / ointment
• שיניים = teeth
• משחת שיניים = toothpaste

The first noun changes form slightly in the construct state:

• משחה → משחת

This is very common in Hebrew noun combinations:

• בית ספר = school (literally house of book)
• מברשת שיניים = toothbrush
• משחת שיניים = toothpaste

Because this is also a construct phrase, and in Hebrew definiteness is usually marked on the second noun in the chain.

So:

• מברשת שיניים = a toothbrush
• מברשת השיניים = the toothbrush

Literally this is something like brush of the teeth, but the natural English meaning is the toothbrush.

In Hebrew construct chains, you usually do not put ה־ on the first word:

• ספר הילד = the boy’s book
• not הספר הילד

So here:

• מברשת השיניים is correct
• המברשת השיניים is not

Because the sentence means:

• toothpaste in general: משחת שיניים
• the toothbrush specifically: מברשת השיניים

So:

• משחת שיניים is indefinite here: toothpaste
• מברשת השיניים is definite: the toothbrush

Hebrew uses definiteness very carefully. If you want to say the toothpaste, you would say:

• משחת השיניים

If you want a toothbrush, you say:

• מברשת שיניים

If you want the toothbrush, you say:

• מברשת השיניים

על means on / onto / upon.

So:

• אני שמה משחת שיניים על מברשת השיניים = I put toothpaste on the toothbrush

This matches English pretty closely.

You may also hear very similar phrasing with a slightly different nuance depending on context, but על is the normal and expected choice here because the toothpaste is being placed on the brush.

Usually yes, or at least it is very natural to include it.

Hebrew present-tense verbs usually do not mark person clearly, so אני helps identify the subject:

• אני שמה = I put
• את שמה = you put (to a woman)
• היא שמה = she puts

Because שמה alone could mean several things, Hebrew commonly keeps the pronoun.

So this sentence sounds normal:

• אחרי שאני מתקלחת, אני שמה...

Not if you want the same meaning.

• אחרי שאני מתקלחת = after I shower
• כשאני מתקלחת = when I shower / while I am showering

So אחרי gives a sequence: first showering, then putting toothpaste on the toothbrush.

כש־ would change the timing and suggest when or while, not after.

Because the sentence begins with a time clause:

• אחרי שאני מתקלחת = After I shower

Then comes the main clause:

• אני שמה משחת שיניים על מברשת השיניים = I put toothpaste on the toothbrush

The comma helps separate these two parts, just like in English:

• After I shower, I put toothpaste on the toothbrush.

In modern Hebrew writing, this comma is normal and helpful.

Only the gender-marked verbs would change:

• אחרי שאני מתקלח, אני שם משחת שיניים על מברשת השיניים.

Changes:

• מתקלחת → מתקלח
• שמה → שם

The nouns stay the same:

• משחת שיניים = toothpaste
• מברשת השיניים = the toothbrush

Here are the main dictionary forms:

• אחרי = after
• אני = I
• להתקלח = to shower
• לשים = to put
• משחה = paste / ointment
• שן = tooth
• מברשת = brush

And in the sentence they appear as:

• מתקלחת from להתקלח
• שמה from לשים
• משחת שיניים from משחה + שיניים
• מברשת השיניים from מברשת + השיניים

This kind of breakdown is especially useful because several of the nouns appear in construct forms rather than their simplest dictionary form.