Chúng ta suýt mở cửa bí mật.

Chúng ta means we including the person being spoken to. It is the inclusive we.

So if I say Chúng ta suýt mở cửa bí mật, I mean you and I / all of us including you almost did that.

By contrast, chúng tôi means we but not including the listener. That is the exclusive we.

Suýt means almost or nearly.

In Vietnamese, it commonly goes before the verb phrase:

• suýt mở = almost opened
• suýt ngã = almost fell
• suýt quên = almost forgot

So the basic pattern here is:

subject + suýt + verb + object

That is why you get Chúng ta suýt mở...

No. Vietnamese often leaves tense unstated if the context is already clear.

In this sentence, suýt already strongly suggests that something nearly happened, so a past-like interpretation is very natural even without đã.

You could add time words if needed:

• Hôm qua, chúng ta suýt mở cửa bí mật.
• Lúc nãy, chúng ta suýt mở cửa bí mật.

But the original sentence is grammatically fine without any tense marker.

Because in Vietnamese, descriptive words usually come after the noun.

So:

• cửa bí mật = secret door
• nhà lớn = big house
• người tốt = good person

This is a very common difference from English, where adjectives usually come before the noun.

It could create some ambiguity, because bí mật can relate to both secret and secretly depending on context.

However, in cửa bí mật, most learners and many native speakers will naturally read it as secret door, because bí mật comes right after cửa and looks like a noun modifier.

If you want to make secret door clearer, cánh cửa bí mật is even better.

If you want to clearly say open the door secretly, Vietnamese would usually make that more explicit, for example with:

• một cách bí mật
• lén lút

So the sentence as written is most naturally understood as referring to a secret door.

Vietnamese usually does not use articles the way English does.

So cửa bí mật can mean:

• a secret door
• the secret door

The exact meaning depends on context.

If you want to be more specific, Vietnamese can add other words, for example:

• một cánh cửa bí mật = a secret door
• cánh cửa bí mật đó = that secret door
• cánh cửa bí mật này = this secret door

Both are possible, but they feel slightly different.

• cửa is perfectly normal and common
• cánh cửa sounds a bit fuller and more concrete, especially for a physical door

In a sentence like this, many speakers would find cánh cửa bí mật slightly more natural if the meaning is literally secret door.

So:

• Chúng ta suýt mở cửa bí mật. = understandable
• Chúng ta suýt mở cánh cửa bí mật. = often clearer and more natural

Yes. Mở means open, and cửa means door, so mở cửa is simply open the door.

There is no extra preposition needed.

This is a very common Vietnamese pattern:

• mở cửa = open the door
• đóng cửa = close the door
• mở hộp = open the box

So the structure is straightforward: mở + object.

It is understandable, but many native speakers might prefer a slightly clearer version:

Chúng ta suýt mở cánh cửa bí mật.

That version makes secret door sound more explicit and natural.

So the original sentence is not wrong, but it can feel a little compressed or slightly ambiguous. Adding cánh often improves it.

Both relate to almost.

• suýt + verb is a simple, common pattern

  • Chúng ta suýt mở cánh cửa bí mật.

• suýt nữa adds a bit more emphasis, often like we very nearly...

  • Chúng ta suýt nữa thì mở cánh cửa bí mật.

So in everyday use:

• suýt = shorter, very common
• suýt nữa = more emphatic, often used in spoken language

Both are useful, but suýt mở... is the most direct pattern for learners to remember.