Mama hupumzika mchana nyumbani.

No. hu- replaces the subject prefix. So you never say something like a-hupumzika. It’s either:

• Habitual: hupumzika
• Non-habitual with subject agreement: anapumzika, alipumzika, atapumzika, etc.

Yes, but the nuance changes:

• Mama hupumzika mchana nyumbani = Mom usually/typically rests at home in the afternoon (habit/routine).
• Mama anapumzika mchana nyumbani = Mom rests/is resting at home in the afternoon. With na-, context often makes this mean “is resting (now), this afternoon,” though it can also express a general present in some contexts. hu- is the clearest way to convey a habitual routine.

Use the regular negative present with a class-1 subject: ha- … -i. For example:

• Mama hapumziki mchana nyumbani. = Mom does not rest at home in the afternoon. Note: there’s no negative form of hu-. To say “doesn’t usually,” add an adverb of frequency:
• Kwa kawaida, mama hapumziki mchana nyumbani. (As a rule, Mom doesn’t rest in the afternoon at home.)
• Mara nyingi, mama hapumziki… (Most of the time, Mom doesn’t…)

Yes. Both are fine:

• Mama hupumzika mchana nyumbani.
• Mama hupumzika nyumbani mchana. Time-before-place (mchana → nyumbani) is very common and often preferred, but the order is flexible.

mchana is “daytime/afternoon,” roughly from late morning through the afternoon (after asubuhi = morning and before jioni = evening). For late afternoon, some varieties use alasiri. Useful related words:

• asubuhi = morning
• jioni = evening
• usiku = night
• mchana kutwa = all day long

Swahili has no articles, so Mama could be “Mom,” “a/the mother,” or a respectful way to refer to a woman—context decides. To be explicit:

• mama yangu = my mother
• mama yako = your mother In conversation, Mama alone often implies “Mom” if you’re talking about your own mother.

Common options:

• Wamama hupumzika mchana nyumbani. (mothers/women)
• Akinamama hupumzika mchana nyumbani. (group of mothers/women) All still use hu- for habitual; it doesn’t change with number.

Use nyumbani plus a possessive pronoun with -ke/-ngu/-ko/-etu/-enu/-ao, or use kwa- phrases:

• nyumbani kwake = at her/his home
• nyumbani kwangu = at my home
• nyumbani kwao = at their home

pumzika is intransitive (to rest). If you need a direct object (to give someone a rest / to put someone to rest), use the causative pumzisha:

• Mama anampumzisha mtoto. = Mom is settling the child to rest. With hu-, object markers are fine: Mama humpumzisha mtoto mara nyingi. (Mom usually settles the child to rest.)

Yes. huwa is a very common adverb meaning “usually/it is usual that” and works with normal verb tenses:

• Mama huwa anapumzika mchana nyumbani. = Mom usually rests at home in the afternoon. Compared to hu-, huwa is stylistically versatile and can combine with different tenses. hu- is a compact, specifically habitual marker on the verb itself.