a tacit understanding的用法和样例：
- A tacit understanding faces even bigger challenges.
- They have a tacit understanding.
- Yet in the right circumstances a tacit understanding can endure.
- On happy festivals, there must be joyfulness linking between our hearts which are always in with a tacit understanding.
- Lu Tzu-hsiao had grown very aloof, a tacit understanding having been reached between them.
- Agreeability to the Zhijiao can not really affiliated done, always will have a tacit understanding.