| 必须HSK 3 | bì xū | to have to; must; compulsory; necessarily | |
| 无须 | wú xū | need not; not obliged to; not necessarily | |
| 莫须有 | mò xū yǒu | groundless; baseless | |
| 胡须HSK 6 | hú xū | beard; Classifiers: 根 | |
| 须知HSK 6 | xū zhī | key information; instructions; it must be borne in mind |
| 1 | They must carry out the plan. | |
| 2 | We must admit the fact. | |
| 3 | We must accept reality. | |
| 4 | Both parties must sign the contract. | |
| 5 | I must go home as soon as possible. |