Problem: How does the sentence end?

Mark liked drawing so he took art classes instead of music lessons because the 
Answer: art classes he would know what to expect.

Problem: How does the sentence end?

Mary hollered at Monica because 
Answer: Mary was so mad about the blocks falling over into the lake.

Problem: How does the sentence end?

The baseball hit the boy and broke his jaw. His mother warned him the 
Answer: baseball is hard.

Problem: How does the sentence end?

Victoria kept carrying Maria on their shoulders, even after 
Answer:
Victoria found themselves becoming tired of holding them up.