Learn Hardcore Chinese: nǐ kěyǐ bǎ nǐ de shǒujīhào xiě gěi wǒ ma? - Could you write your phone number down for me?

你的手机号 is brought in front with 把 to mark it as the thing being acted on.
The verb phrase 写给我 shows what you do to it: you write it (and give it to me).

A loose way to feel it in English is:

“Can you take your phone number and write it down for me?”

So 把 adds focus to 你的手机号 as the “target” of the action and makes the sentence sound natural and smooth.

Can I just omit 把 and say the same thing?

Yes, you can omit 把, and the sentence is still natural. For example:

你可以写你的手机号给我吗？
你可以给我写你的手机号吗？

These are both fine and commonly used. The differences:

With 把: 你可以把你的手机号写给我吗？
- Slightly more emphasis on the phone number as the thing handled/disposed of.
- Common, very natural.
Without 把:
- 你可以写你的手机号给我吗？
  Pattern: 写 + object + 给 + recipient
- 你可以给我写你的手机号吗？
  Pattern: 给 + recipient + 写 + object

All three are acceptable; the 把-version is just one natural option among several.

What exactly does 给 do in 写给我?

Here 给 marks the recipient of the action, similar to “to / for” in English.

写 = to write
写给我 = to write (it) to me / for me

So 写给我 literally means “write (something) and give it to me,” or more naturally “write it down for me.”

You cannot say 写我 to mean “write to me”; you need 给:

❌ 写我你的手机号
✅ 写给我你的手机号
✅ 写你的手机号给我

Without 给, 我 would look more like a direct object (write me) rather than a recipient.

Is the word order fixed? Why not 写给我你的手机号 or 写我你的手机号?

Several word orders are possible, but some are much more natural:

Natural patterns:

写 + object + 给 + recipient
- 写你的手机号给我
给 + recipient + 写 + object
- 给我写你的手机号
把 + object + 写给 + recipient
- 把你的手机号写给我

Less natural / awkward:

写给我你的手机号
- Understandable, but Chinese prefers to keep 给 + recipient and object closer to the verb in clearer patterns like the ones above.

Wrong:

写我你的手机号
- ❌ because 写我 would mean “write me,” and Chinese doesn’t work that way; it needs 给 to introduce the recipient.

So the original 把你的手机号写给我 follows a very typical and smooth pattern.

What does 的 do in 你的手机号? Could I say 你手机号 instead?

的 is the possessive particle, like “’s” or “of”:

你 = you
你的 = your
你的手机号 = your phone number

In casual spoken Chinese, 的 can be dropped with some possessors, especially with close relations or very common combinations:

我妈妈 → 我妈
你朋友 (instead of 你的朋友) — colloquial but heard

For 你的手机号, you might hear 你手机号 in informal speech, but:

你的手机号 is the standard and safest form.
你手机号 is more casual, and not appropriate in all contexts.

For learners, sticking with 你的手机号 is a good idea.

Why isn’t there a measure word (like 个) between 你的 and 手机号?

Measure words are used when you count or quantify nouns, e.g.:

一个手机号 = one phone number
三个手机号 = three phone numbers

But when you just refer to the noun in general without counting it, you usually don’t need a measure word:

你的手机号 = your phone number
我的名字 = my name
他的地址 = his address

So in this sentence, we are not counting, just talking about “your phone number” as a thing, so no measure word is needed.

Why is 你 at the beginning if we already have 你的 later? Could we drop the first 你?

The first 你 is the subject (“you”), and 你的 is the possessor (“your”).

你 (subject) 可以 … 吗？ → YOU may…?
你的手机号 → YOUR phone number

You can omit the subject in Chinese if it’s obvious from context. So:

可以把你的手机号写给我吗？

is also grammatical and natural, assuming the listener knows you’re talking to them.

Including the first 你:

Makes the sentence slightly more explicit and complete.
Is very common in full, clear sentences (especially in teaching materials).

Both versions can be heard; omitting 你 is just a bit more colloquial and context‑dependent.

What level of politeness does this sentence have? Is it polite enough?

你可以把你的手机号写给我吗？ is polite and normal in most informal situations. It uses:

可以…吗？ → a polite request structure
No rude wording or harsh tone

To make it even more polite/soft, you can add elements like:

请你把你的手机号写给我，可以吗？
麻烦你把你的手机号写给我，好吗？
你可以把你的手机号写给我一下吗？

To make it more casual / direct, you might say:

把你的手机号写给我。 (plain imperative; can sound blunt depending on tone)
把你的手机号给我写一下。

So the original sentence is politely phrased and suitable for neutral / friendly contexts.

Why do we put 吗 at the end? Could we use 呢 or 吧 instead?

吗 is the yes‑no question particle. Adding 吗 to a statement turns it into a question expecting “yes / no”:

你可以把你的手机号写给我。 = You can write your phone number down for me. (statement)
你可以把你的手机号写给我吗？ = Can you write your phone number down for me? (question)

Other particles:

呢
- Often used for follow‑up questions (“What about…?”) or to show continuation of a topic.
- 你呢？ = “And you?”
- Using 呢 here would not give the straightforward yes‑no request meaning.
吧
- Soften a suggestion or command: “..., okay?” / “let’s …”
- 把你的手机号写给我吧。 → more like “Go ahead and write your phone number for me, okay?”
- Implies you kind of expect the person to comply.

So for a direct yes‑no request, 吗 is the correct and standard choice.

Where could I put 一下 if I want to sound even more polite or casual?

一下 softens the verb, making the action sound brief and less imposing, like “(just) a bit / for a moment.”

You can place 一下 near the main verb 写:

你可以把你的手机号写一下给我吗？
你可以把你的手机号写给我一下吗？

Both are heard in speech; many speakers prefer 写一下给我 because it keeps 一下 right after the main verb.

Meaning‑wise, they all convey: “Could you just quickly write your phone number down for me?”

Could I say 请你把你的手机号写给我 without 吗?

Yes.

请你把你的手机号写给我。
is a polite imperative: “Please write your phone number down for me.”

Differences:

With 吗:
- 你可以把你的手机号写给我吗？
- Grammatically a question, feels like asking for permission/possibility.
With 请 and no 吗:
- 请你把你的手机号写给我。
- Grammatically a request/command, but “请” keeps it polite.

Both are polite; the 吗 version feels more like a question; the 请 version feels more like a courteous instruction.

What’s the difference between 手机号, 手机号码, and 电话号码?

They are related but not identical:

手机号
- Short for 手机号码.
- Very common in speech.
- Specifically means mobile / cell phone number.
手机号码
- Full form, slightly more formal/complete.
- Also means mobile / cell phone number.
- Often seen in forms, official texts.
电话号码
- Telephone number in general.
- Could be a landline or a mobile number, depending on context.

In everyday conversation, when you’re obviously talking about mobiles, 手机号 is the most natural.

Does 写给我 mean writing it on paper, or can it also mean typing/sending it digitally?

Literally, 写 is “to write,” originally handwriting. But in modern usage:

写给我 can mean:
- Write it on paper for me
- Put it in a note or a message and show/send it to me

If you specifically mean send it to me (by message/app), people commonly say:

发给我 = send it to me
- 你可以把你的手机号发给我吗？ → “Can you send me your phone number?”

So:

写给我 → focus on the act of writing it down for me (paper or digital).
发给我 → focus on sending it (usually digitally).

Can I replace 写给我 with other verbs like 告诉我 or 发给我?

Yes, different verbs change the mode of giving the number:

写给我
- Write it down and give it to me (paper or text).
告诉我
- Tell me (usually spoken).
- 你可以把你的手机号告诉我吗？ → “Can you tell me your phone number?”
发给我
- Send it to me (message, app, email).
- 你可以把你的手机号发给我吗？ → “Can you send me your phone number?”

The 把 + 你的手机号 + [verb] + 给我 structure can work with many verbs where it makes sense:

留给我 (leave it for me)
写下来给我 (write it down and give it to me)

The original chooses 写给我 to emphasize writing it down for you.