Question

1. Sheela baked a cake for her mother's birthday. [Rewrite the sentence
using the past perfect tense of the verb]​

Answer 1

Sheela had baked a cake for her mother's birthday.

Hope it helps.....^•^

Answer 2

Sheela had baked a cake for her mother's birthday.

• The past perfect tense is used to refer to an action that has been occurred as well as at some point of time in the past.
• The structure of a sentence in past perfect tense is as follows:- Subject + had + third form of the verb.
• In the given case, 'had baked' is the third form of the verb 'bake.'  
• So the sentence will change to "Sheela had baked a cake for her mother's birthday."