| 走私HSK 6 | zǒu sī | to smuggle; to have an illicit affair | |
| 私人HSK 5 | sī rén | private; personal; interpersonal; sb with whom one has a close personal relationship; a member of one's clique | |
| 私营 | sī yíng | privately-owned; private | |
| 无私 | wú sī | selfless; unselfish; disinterested; altruistic | |
| 私下 | sī xià | in private |
| 1 | Maternal love is selfless. | |
| 2 | These goods were smuggled in. | |
| 3 | He is funny but a little selfish. | |
| 4 | We should protect our own privacy rights. | |
| 5 | We promise to maintain user privacy. |