Helen's work at the Central Post Office was not very interesting, but she (have) to give her full attention to the address which (write) on each letter. She (know) that if she (put) the letter in the wrong box, it never (reach) the right person. But now Helen (hold) one strange letter in her hands. She (see) it (address) to her, but she couldn't understand who (write) it, as the handwriting was illegible. "I never before (see) such a mess of writing!"