| I | tighten |
|---|---|
| you | tighten |
| he/she/it | tightens |
| we | tighten |
| you | tighten |
| they | tighten |
| I | tightened |
|---|---|
| you | tightened |
| he/she/it | tightened |
| we | tightened |
| you | tightened |
| they | tightened |
| I | have | tightened |
|---|---|---|
| you | have | tightened |
| he/she/it | has | tightened |
| we | have | tightened |
| you | have | tightened |
| they | have | tightened |
| I | had | tightened |
|---|---|---|
| you | had | tightened |
| he/she/it | had | tightened |
| we | had | tightened |
| you | had | tightened |
| they | had | tightened |
单语范例（未经PONS编辑处理）
The guitar has 24 frets and the strings are tightened through the body.
en.wikipedia.org Security was again tightened, with 9,000 police deployed in three layers of security at the 13 counting centres within the 12 districts.
en.wikipedia.org The knit tightens, creases are eliminated and the leg is correctly shaped.
en.wikipedia.org The security at the embassy was tightened in the early 1980s, when the embassy was burned to the ground in 1979 by extremists.
en.wikipedia.org It supports economic integration and tightening the cooperation in areas of energetic security and military, but is skeptical about closer political integration.
en.wikipedia.org