Problem: How does the sentence end?

Christopher wasn't a plumber but he knew Matthew was so 
Answer: Christopher called him to fix his sink.

Problem: How does the sentence end?

I would like to learn to ride a bicycle rather than a unicycle. To learn to ride the 
Answer: bicycle is easy.

Problem: How does the sentence end?

The new bicycle Jill purchased for herself would not fit through her front doorway, the 
Answer: bicycle was too wide.

Problem: How does the sentence end?

Adam came over to Samuel's house to warm up with a cup of hot chocolate, since 
Answer:
Adam 's heater was broken.