Мама купила печенье в виде сердца.

to buy

Breakdown of Мама купила печенье в виде сердца.

• мама: the mother
• сердце: the heart
• печенье: the cookie

Questions & Answers about Мама купила печенье в виде сердца.

Why does мама by itself mean my mom here? Where is моя?

Russian often omits possessive pronouns (мой, моя, моё, мои) with close family members when it is obvious whose family member is meant.

So:

• Мама купила печенье.
  = Mom bought cookies / My mom bought cookies.

It usually refers to the speaker’s mother unless context clearly says otherwise.
If you add моя (Моя мама купила…), it sounds a bit more emphatic or contrastive: My mom (not someone else’s) bought… but it’s not required for the basic meaning.

What does the verb купила tell us about tense, aspect, and gender?

Купила is:

• Past tense
• Singular
• Feminine
• Perfective

From the verb pair:

• покупать – to buy (imperfective)
• купить – to buy (perfective)

Past-tense endings:

• masculine: купил
• feminine: купила
• neuter: купило
• plural: купили

Because the subject мама is feminine, the verb must be купила.
Perfective past (купила) usually describes a completed, one-time action: she bought it (and it’s done).

What is the difference between and in this kind of sentence?