| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | [prep] [noun pl] ' national insurance | 11 |
|
| 2 | [prep] [noun pl] ' national insurance | 11 |
|
| 3 | [prep] [noun pl] ' national insurance | 11 |
|
| 4 | [prep] employers ' national insurance | 6 |
|
| 5 | [prep] employees ' national insurance | 5 |
|
| 6 | on [noun pl] ' national insurance | 5 |
|
| 7 | on [noun pl] ' national insurance | 5 |
|
