1.I require that the contract should be made in black and white.
2.The ancient tower, dating back to the 16th century, is now being repaired.
3.When I referred to that matter, I didn't mean to hurt you.
4.Nowadays people have to rely upon computers to carry out work.
5.I write you in reference to the job that your company is advertising.
6.A trained dog can take on the guiding responsibility well to help his owner walk around safely.