Put questions to the italicized words. 1. He is going to visit his aunt and uncle at the weekend (2 предложения).
2. They are going to spend their weekend in Spain (2 предложения).
3. My Mom is going to make a cake for my birthday (2 предложения).

1. who is he going to visit?

when is he going to visit your aunt and uncle?

2. where do they want to spend the weekend?

How many days do they plan to spend in Spain?

3. what does mom want to bake for my birthday?

what does she want to make a cake for?

1. He is going to visit his "aunt and uncle at the weekend" .

Whom is he going to visit at the weekend?

When is he going to visit his aunt and uncle?

2. "They" are going to spend their weekend "in Spain".  

Who is going to spend a weekend in Spain?

Where are they going to spend their weekend?

3. "My" Mom is going to make "a cake" for my birthday.

Whose mom is going to make a cake for my birthday?

What is my Mom going to make for my birthday?

"Mom" is American English ( "mum" in British English)