Mama anasema mchuzi huu ni mzito sana.

Anasema can be broken into three parts:

• a- = subject marker for he/she or a singular person noun such as Mama
• -na- = present tense marker
• -sema = verb root meaning say / speak

So anasema means she says or she is saying, depending on context.

Because Swahili usually puts the subject information inside the verb.

In anasema, the a- already tells you the subject is he/she. Since Mama is already named, Swahili does not need an extra separate pronoun.

So:

• Mama anasema = Mother/Mom says
• literally, the verb already contains the she

In Swahili, demonstratives like this usually come after the noun, not before it.

So:

• mchuzi huu = literally sauce this
• natural English: this sauce

This noun + demonstrative order is very normal in Swahili.

Because Swahili demonstratives must agree with the noun class of the noun they describe.

Mchuzi belongs to noun class 3 in the singular, so the matching form for this is huu.

That is why you get:

• mchuzi huu = this sauce

If the noun belonged to a different class, the word for this would change.

For the same reason: adjective forms in Swahili often agree with the noun class.

The basic adjective idea is -zito, meaning heavy.
With mchuzi (class 3 singular), it becomes:

• m-zito = mzito

So:

• mchuzi huu ni mzito = this sauce is thick/heavy

The m- is the agreement prefix.

Ni is the copula here, meaning roughly is.

So:

• mchuzi huu ni mzito = this sauce is thick/heavy

It links the subject mchuzi huu with the description mzito.

Sana usually comes after the word it is strengthening.

Here it strengthens mzito:

• mzito sana = very thick / very heavy

This word order is normal in Swahili:

• adjective + sana
• verb + sana
• adverb + sana

Not literally. Mzito basically means heavy. But in context, it can also describe something thick, dense, or rich.

So with mchuzi (sauce/gravy), English often translates it as:

• thick
• sometimes too heavy/rich, depending on context

So the Swahili word is broader than just one English word.

Mchuzi is singular in class 3.
Its plural is michuzi, which is class 4.

When you change to the plural, the agreement words change too:

• mchuzi huu ni mzito sana = this sauce is very thick
• michuzi hii ni mizito sana = these sauces are very thick

Notice the changes:

• mchuzi → michuzi
• huu → hii
• mzito → mizito

Swahili does not normally use articles like English a/an/the.

Whether something is definite or indefinite usually comes from:

• context
• demonstratives like huu = this
• possessives
• other modifiers

So mchuzi huu already clearly means this sauce, without needing a separate word for the.