1, mainly depends on the requirements of the tender documents. It is usually stipulated that the parts that need to be signed and sealed are not required to be covered, but it is recommended to cover every page to avoid falling and crying. 2. A copy is a copy of the original. The original is covered, and the copy can be copied. No separate coverage is required. 3, page-by-page coverage is the safest, so the qualification class still needs to be covered, not bad. PS: What project are you working on? Some are stricter and some are looser.