Loại này rất tốt.

In this sentence, loại means type, kind, or category.

So Loại này means this type or this kind.

It is often used when talking about products, materials, styles, medicines, foods, and other things that come in different varieties.

In Vietnamese, demonstratives like này (this) usually come after the noun.

So:

• loại này = this type
• literally: type this

This is normal Vietnamese word order.

No. Vietnamese often leaves out the verb to be in sentences like this.

So Loại này rất tốt literally looks like:

• Loại này = this type
• rất = very
• tốt = good

Natural English adds is: This type is very good.

Rất means very. It is an adverb that intensifies the adjective after it.

So:

• tốt = good
• rất tốt = very good

It comes before the adjective, just like very in English.

Yes. Tốt is a very common adjective meaning good, but depending on context it can also suggest:

• high quality
• beneficial
• effective
• kind or morally good

In Loại này rất tốt, the most natural meaning is that this type is very good or of very good quality.

Yes, but it depends on context.

Loại này is natural when you are comparing types or kinds of something. For example, in a shop, while discussing medicine, coffee, fabric, or phone chargers, Loại này rất tốt sounds normal.

If you are pointing to a specific object rather than a type/category, Vietnamese might more naturally use:

• Cái này rất tốt = this one is very good

So loại focuses on type/kind, while cái này often focuses on this item/this thing.

They are not the same.

• loại = type, kind, category
• cái = a very common classifier for objects

Compare:

• Loại này rất tốt = This type is very good.
• Cái này rất tốt = This one/this thing is very good.

A learner should notice that loại adds a meaning of classification, not just reference to an object.

A careful pronunciation is approximately:

Loại này rất tốt
≈ lwah-ee nigh zut tote (very approximate)

A few notes:

• loại has a gliding vowel sound and a falling-glottal contour because of its tone
• này rhymes roughly with English eye, but starts with n
• rất ends with t, so the final consonant is unreleased
• tốt also ends with t

The exact pronunciation depends somewhat on dialect.

The tones are:

• loại: nặng tone
• này: huyền tone
• rất: sắc tone
• tốt: sắc tone

Tones are essential in Vietnamese, so changing them can change the word entirely.

You can use that as a learning aid, but not as a real translation.

A more natural breakdown is:

• Loại này = this type
• rất tốt = very good

So the natural English sentence is This type is very good or This kind is very good.

It is generally neutral and very usable in everyday conversation.

It is not especially formal, but it is also not slangy. You could say it in a store, during a recommendation, or in ordinary conversation.

You could soften it in several ways, for example:

• Loại này tốt. = This type is good.
• Loại này khá tốt. = This type is quite good.
• Loại này cũng tốt. = This type is also good / pretty good depending on context.

So rất makes the praise stronger.

You can put không before the adjective:

• Loại này không tốt. = This type is not good.

You can also say:

• Loại này không được tốt lắm. = This type is not very good.

That version sounds a bit softer or less blunt.