wǒmen xiān chīfàn, zài qù gōngyuán sànbù ba.

先...再... is a very common pattern for putting actions in order. It means first... then....

So:

• 我们先吃饭 = we first eat / we’ll eat first
• 再去公园散步 = then go to the park for a walk

It is one of the easiest ways in Mandarin to show sequence.

Yes, 再 can mean again, but here it means then / after that.

In this sentence, 再 is used to show the next step in a planned sequence:

• 先吃饭，再去公园散步
• first eat, then go walk in the park

This is especially common when talking about future actions, plans, or suggestions.

A useful comparison:

• 再 = again / then, often for future or next-step actions
• 又 = again, often for repeated actions in the past or present

So here 再 is the natural choice.

吃饭 is a very common expression meaning to eat a meal / have a meal.

Even though 吃 alone means eat, Mandarin often uses 吃饭 when talking about eating in a general everyday sense.

So:

• 吃 = eat
• 吃饭 = eat a meal / have a meal

In normal conversation, 吃饭 often sounds more complete and natural than just 吃.

Grammatically, it is a verb-object structure:

• 吃 = eat
• 饭 = rice / meal / food in this expression

But for learners, it is often easiest to treat 吃饭 as a common chunk meaning have a meal.

This matters because verb-object phrases in Mandarin can often be separated or modified, for example:

• 吃了饭
• 吃完饭
• 吃早饭

So it is not a single indivisible word in the strictest grammar sense, even though it often behaves like a set phrase in basic sentences.

Because 公园 is the destination of 去.

• 去公园 = go to the park

You use 在 when you mean at/in a place:

• 在公园散步 = take a walk in the park

In this sentence, the structure is:

• 去公园散步 = go to the park to take a walk

So 公园 comes directly after 去 because it is where you are going.

The sentence uses this pattern:

• 去 + place + verb

So:

• 去公园散步 = go to the park and take a walk = more literally, go to the park to walk

This is a very common Mandarin structure when you go somewhere in order to do something.

Other examples:

• 去商店买东西 = go to the store to buy things
• 去图书馆看书 = go to the library to read

So 公园 tells you where, and 散步 tells you what you will do there.

吧 makes the sentence sound like a suggestion, proposal, or gentle invitation.

So:

• 我们先吃饭，再去公园散步吧。

means something like:

• Let’s eat first, then go for a walk in the park.
• How about we eat first, then go for a walk in the park?

Without 吧, the sentence can sound more like a plain statement of plan. With 吧, it becomes softer and more natural as a suggestion.

In Mandarin, 我们...吧 is a very common way to express let’s...

So:

• 我们先吃饭吧 = let’s eat first

Even though 我们 literally means we, the combination with 吧 often gives the meaning of a suggestion that includes the listener.

A related word is 咱们, which very explicitly includes the listener:

• 咱们先吃饭，再去公园散步吧

This also sounds very natural and a bit more conversational in many contexts. But 我们 is completely correct here.

Yes, very often.

Mandarin frequently leaves out the subject when it is clear from context. So you could also say:

• 先吃饭，再去公园散步吧。

This still sounds natural if everyone already knows who is involved.

Including 我们 just makes the subject explicit.

The comma is helpful, but it is not the core of the grammar.

It marks a pause between the two parts:

• 我们先吃饭，
• 再去公园散步吧。

This makes the sequence easier to read. In speech, you would usually pause slightly there too.

So the comma is normal and useful in writing, especially with 先...再... structures.

Both 们 in 我们 and 吧 are usually pronounced with a neutral tone here:

• 我 = wǒ
• 们 = men (neutral)
• 吧 = ba (neutral)

So:

• 我们 = wǒmen
• 吧 = ba

This lighter pronunciation is very common in natural speech.

Yes, but the meaning changes.

The original sentence says:

• first eat
• then go to the park for a walk

If you say:

• 我们先去公园散步，再吃饭吧。

that means:

• Let’s go for a walk in the park first, then eat.

So the grammar still works, but the sequence is different. The words 先 and 再 clearly control the order.

Yes. The pattern stays the same, and you can swap in another activity:

• 我们先吃饭，再去公园跑步吧。 = Let’s eat first, then go to the park to run.

• 我们先吃饭，再去公园聊天吧。 = Let’s eat first, then go to the park to chat.

• 我们先吃饭，再去公园玩吧。 = Let’s eat first, then go to the park to hang out / play.

This makes the sentence a very useful model for building your own plans and suggestions.