Говори мягче, пожалуйста.

Говори is the imperative form, used to tell someone to do something: speak.

• говорить = to speak
• говоришь = you speak / you are speaking
• говори = speak!

So Говори мягче, пожалуйста. is a request or command.

Yes. Говори is the informal singular imperative, used with:

• one person you address as ты
• someone you know well
• a child
• sometimes a subordinate, depending on context

For a more formal version, or when speaking to more than one person, use говорите:

• Говорите мягче, пожалуйста.

So:

• говори = informal, one person
• говорите = formal one person or plural

Russian often leaves out the subject when it is obvious.

In an imperative, the person being addressed is already clear from the verb form:

• Говори already means you speak!
• Говорите already means you speak! to a formal singular or plural listener

So adding ты is usually unnecessary unless you want extra emphasis:

• Ты говори мягче. = You, speak more gently.
  This sounds more marked and can feel emphatic.

Мягче means softer, more gently, or less harshly.

It comes from мягкий = soft.

In this sentence, it describes how someone should speak, so in natural English it may be understood as:

• speak more softly
• speak more gently
• speak less harshly

Depending on context, it can refer to:

• volume: don’t speak so loudly or sharply
• tone: be less rude, less severe, less aggressive

Мягко means softly / gently, while мягче means more softly / more gently.

So the sentence is not just saying Speak softly, but rather:

• Speak softer than you are speaking now
• Be gentler in your tone

That comparative idea is very common in Russian requests:

• Тише, пожалуйста. = More quietly / quieter, please.
• Помедленнее. = More slowly.
• Мягче. = More gently / softer.

Historically it comes from the adjective мягкий (soft), but here it functions like an adverbial comparative: it describes the manner of speaking.

So in practice, you can think of it as:

• мягче = more softly / more gently

Russian often uses comparative forms this way without a separate adverb ending.

Yes. It can mean several related things depending on context.

Possible shades of meaning:

• Speak more quietly
• Use a gentler tone
• Don’t sound so harsh
• Be more tactful

If someone is being emotionally sharp, мягче may refer more to tone than to volume.

This is about the difference between говорить and сказать.

• говорить focuses on the process or manner of speaking
• сказать usually focuses on saying something конкретely / one time

So:

• Говори мягче = Speak more gently / Use a gentler way of speaking
• Скажи мягче would sound more like Say it in a gentler way

In this sentence, the speaker is commenting on the person’s manner of speech, so говори is the natural choice.

Пожалуйста adds politeness, like please.

Its position is flexible in Russian. These are all possible:

• Говори мягче, пожалуйста.
• Пожалуйста, говори мягче.
• Говори, пожалуйста, мягче.

The version you have sounds very natural.

Even with пожалуйста, though, the sentence can still sound fairly direct, especially if said with strong intonation.

The stress is on the first syllable:

• мЯгче

A rough guide for English speakers:

• MYAKH-che or MYAG-che

A few pronunciation notes:

• я after м makes the м sound soft
• гч in real speech is often pronounced more like хч or a softened cluster
• the final -че sounds like che

So don’t try to pronounce it exactly letter-by-letter as a hard g.

Not necessarily, but it is fairly direct.

Tone depends on:

• intonation
• relationship between speakers
• situation

Compare:

• Говори мягче. = direct, could sound strict
• Говори мягче, пожалуйста. = softer and more polite
• Говорите мягче, пожалуйста. = more polite/formal

So the sentence can range from caring advice to a firm correction.

You can understand it that way, but in natural English, better translations are usually:

• Speak more softly, please.
• Speak more gently, please.
• Please speak more softly.
• Please be gentler in the way you speak.

Softer by itself in English is understandable, but more softly is usually more natural when describing speaking.

The base form is мягкий = soft.

The comparative is мягче = softer / gentler.

Yes, the formation is not as transparent as simply adding one ending to the full adjective stem, so learners often just memorize it:

• мягкий → мягче

This is normal in Russian. Many comparatives have stem changes or special forms.