Máy điều hòa và bóng đèn còn tốt.

Vietnamese often does not use a verb like to be in simple descriptions.

So where English says:

• The air conditioner and the light bulb are still good

Vietnamese can simply say:

• Máy điều hòa và bóng đèn còn tốt

Here, tốt works as the predicate meaning good / in good condition / working well, and no separate are is needed.

In this sentence, còn means still.

So còn tốt means:

• still good
• still in good condition
• still usable
• sometimes still working fine, depending on context

This is a very common use of còn.

For example:

• Cái bàn còn chắc. = The table is still sturdy.
• Xe còn mới. = The vehicle is still new.

Be careful: còn has other meanings too, such as remaining, left, or sometimes but/as for in other structures. But here it clearly means still.

Because in Vietnamese, tốt is often used broadly for the condition or quality of a thing.

With objects like appliances, tốt can mean:

• good
• in good condition
• working properly
• not broken

So bóng đèn còn tốt does not just mean the bulb is morally or abstractly “good.” It means the bulb is still fine / still usable / still works.

This kind of broad adjective use is very normal in Vietnamese.

Usually bóng đèn means light bulb.

But in everyday use, people may sometimes use it a bit loosely depending on context, especially when talking about lighting in general.

More specifically:

• bóng đèn = light bulb
• đèn = light / lamp
• đèn điện = electric light/lamp

In your sentence, the most natural understanding is light bulb.

Because classifiers are often omitted when you are speaking generally or making a simple statement about things.

So:

• Máy điều hòa và bóng đèn còn tốt = natural
• Cái máy điều hòa và cái bóng đèn còn tốt = possible, but more specific or conversational

Using classifiers can make the sentence feel more like you are pointing to particular objects or speaking in a more concrete way.

In many neutral statements, Vietnamese just uses the noun directly.

It is a noun phrase:

• máy = machine/device
• điều hòa = regulating/balancing, and in modern usage refers to air conditioning

Together, máy điều hòa means air conditioner.

In everyday speech, many people shorten it to just:

• điều hòa

So you may also hear:

• Điều hòa và bóng đèn còn tốt.

That is very common in spoken Vietnamese.

Because the conjunction và already links two nouns:

• máy điều hòa = air conditioner
• bóng đèn = light bulb
• và = and

So the structure itself makes it clear that there are two items.

Vietnamese usually does not change adjectives or verbs for singular vs. plural. The sentence stays the same:

• Máy điều hòa còn tốt. = The air conditioner is still good.
• Máy điều hòa và bóng đèn còn tốt. = The air conditioner and the light bulb are still good.

No extra agreement is needed.

Because Vietnamese often puts the description after the subject.

The basic pattern here is:

• Subject + predicate
• Máy điều hòa và bóng đèn
  • còn tốt

So the sentence literally follows a pattern like:

• Air conditioner and light bulb + still good

This is normal Vietnamese word order for describing the state or condition of something.

Yes, vẫn tốt is possible in many contexts, and it also means still good.

However, there is a slight nuance:

• còn tốt often suggests it remains in good condition
• vẫn tốt often stresses it is still good despite time/change/expectation

In many everyday situations, both work.

Examples:

• Máy điều hòa và bóng đèn còn tốt.
• Máy điều hòa và bóng đèn vẫn tốt.

Both are natural, but còn tốt is especially common when talking about whether items are still usable.

Yes, it is natural and clear.

It sounds like something you might say when checking the condition of household items, for example during:

• a move
• an inspection
• buying/selling used things
• describing what in a room still works

Depending on context, a native speaker might also say:

• Máy điều hòa và bóng đèn vẫn còn tốt.
• Máy điều hòa với bóng đèn còn tốt.

But your original sentence is perfectly normal.

A learner may want to watch these parts carefully:

• máy — rising tone
• điều — low/falling kind of tone
• hòa — falling tone
• và — low tone
• bóng — rising tone
• đèn — low/falling tone
• còn — falling tone
• tốt — high broken/glottalized tone

A big point for learners: tốt and tôt would not be the same, and tone mistakes can make you harder to understand. Also, đ in điều hòa and đèn is a separate letter from d in Vietnamese.

If you want the sentence in chunks for pronunciation, try:

• Máy điều hòa / và bóng đèn / còn tốt.

That rhythm sounds natural.