Zhǐyǒu dìzhǐ xiě de duì, kuàidì cái huì sòngdào wǒ jiā.

It means only if... then... or only when... will....

In this sentence:

• 只有地址写得对 = only if the address is written correctly
• 快递才会送到我家 = then the delivery/package will get sent to my home

This pattern expresses a necessary condition. The second part happens only under that condition.

A rough English structure is:

• Only if X, will Y
• Y will happen only if X

才 works together with 只有.

• 只有 introduces the condition
• 才 marks the result that happens only then

So 才 is important because it shows restriction: the package will arrive at your home only in that case, not otherwise.

Without 才, the sentence would sound incomplete or at least would lose the standard 只有...才... structure.

Here, 得 is the particle used to introduce a complement after a verb.

Structure:

• 写 = write
• 得 = complement marker
• 对 = correct / correctly

So 写得对 means written correctly or write it correctly.

This is the common pattern:

• verb + 得 + complement

Examples:

• 说得很好 = speak very well
• 做得对 = do it correctly
• 写得对 = write it correctly / be written correctly

Both can be correct, but they are not exactly the same.

• 写对 often emphasizes the result: you wrote it correctly, you got it right.
• 写得对 describes how correctly it is written or evaluates the writing as correct.

In this sentence, 地址写得对 sounds natural because it describes the address as being written correctly.

So:

• 地址写对了 = the address was successfully written correctly
• 地址写得对 = the address is written correctly

For this kind of condition sentence, 写得对 works very well.

Chinese often leaves out subjects when they are obvious or unimportant.

Here, 地址写得对 literally looks like the address is written correctly. It does not need to say who wrote it, because that detail is not the focus.

The focus is the condition itself:

• if the address is correct as written,
• then the delivery can reach my home.

This kind of omission is very normal in Chinese.

会 here means something like will, can be expected to, or is likely to.

In this sentence, it helps express the result:

• 快递才会送到我家 = only then will the package be delivered to my home

Chinese does not have a strict future tense in the same way English does, so 会 often adds a sense of:

• future
• likelihood
• expected outcome

If you removed 会, the sentence could still be understandable, but 才会 sounds very natural here.

快递 can mean several related things depending on context:

• express delivery service
• courier
• package / parcel delivered by courier

In this sentence, 快递 most naturally refers to the package or the delivery item.

So in natural English, this sentence would often be understood as:

• Only if the address is written correctly will the package be delivered to my home.

Chinese often uses 快递 in this broad way, where English might choose package, parcel, or delivery depending on the situation.

送到 means deliver to / send to and reach.

Breakdown:

• 送 = send / deliver
• 到 = reach, arrive at

So 送到我家 means deliver it to my home or send it so that it arrives at my home.

The 到 is important because it shows the action reaches the destination.

Compare:

• 送我家 = not natural here
• 送到我家 = deliver to my home

This verb + 到 pattern is very common in Chinese.

In everyday Chinese, 我家 is much more natural.

Chinese often omits 的 in very common, close relationships or familiar expressions, such as:

• 我妈 = my mom
• 我朋友 = my friend
• 我家 = my home / my family / my place

我的家 is grammatically possible, but it often sounds more emphatic, emotional, or literary, like my home in a more expressive sense.

In this sentence, 送到我家 is the normal everyday way to say deliver it to my home.

Not if you want the same meaning.

These two patterns are different:

• 只要...就... = as long as... then...
• 只有...才... = only if... then...

只有...才... is more restrictive.

So:

• 只有地址写得对，快递才会送到我家。
  = Only if the address is written correctly will the package arrive at my home.

If you changed it to 只要...就..., it would sound more like:

• As long as the address is written correctly, the package will arrive at my home.

That is similar, but not exactly the same in force. 只有...才... strongly emphasizes that this is the necessary condition.

对 is the most common everyday word for correct / right.

So 写得对 sounds natural and conversational.

正确 also means correct, but it is often a bit more formal. For example:

• 地址写得正确 is understandable
• but 地址写得对 sounds more natural in everyday speech

Chinese often prefers short, common words like 对 in ordinary conversation.

Yes, in meaning it is somewhat passive, even though there is no explicit passive marker like 被.

地址写得对 means the address is written correctly.
快递才会送到我家 means the package will be delivered to my home.

Chinese often allows this kind of passive-like meaning without using a special passive form, especially when the doer is not important.

So the sentence sounds very natural even though it does not say exactly who writes the address or who delivers the package.

The given order is natural and standard.

Chinese often puts the condition first and the result after:

• 只有地址写得对，快递才会送到我家。

That is the clearest form.

You can sometimes rephrase it, but the original is the most straightforward. For a learner, it is best to remember the core pattern as:

• 只有 + condition, + result + 才...

So this sentence is a very good model for that structure.