秘密制造过程

例句：

1. 1. They were secretly meeting inthe park every evening.
   他们每天晚上都在公园秘密会面。
2. 2. She was secretly watching himfrom a distance.
   她偷偷地从远处看着他。
3. 3. The plan was secretly hatchedby the team.
   这个计划是团队秘密策划的。