Question

1) The criminal will be arrested.
End:______________the criminal.

2) The rats gave us a lot of trouble.
Use troublesome instead of trouble.
_____________________.

Answer 1

1)The criminal will be arrested.

End:______________the criminal.

The criminals are arrested by the police. Thus, the answer is -The police will arrest the criminal.  

2)The rats gave us a lot of trouble.  

By Using troublesome instead of trouble.

The new sentence will be- The rats were a great troublesome for us.

Answer 2

1. The criminal will be arrested - this sentence will become - Someone will arrest the criminal.

2. The rats gave us a lot of trouble - this sentence will become - The rates were troublesome for us.

These two sentences are simple, and the question is asked to change the formation of the existing sentence only.