"Sealing the title" refers to signing the title at the sealing place after the goods are properly packed. This refers to adding a label or signature to the seal after the goods are packaged.
2. Especially on the seal of the book. This refers to adding a signature or seal to the seal of a letter or document to prove its authenticity and integrity.
3. Pronouns extended to letters. This refers to the use of "titles" to refer to letters or documents in general.
4, it is still sealed. This means that "sealing the title" can also be used as a synonym for "sealing the performance", which refers to the submission of documents or reports to superiors.