| behooves(verb, must, should, requires, behoves) |
| have to(verb, expression, must, should, requires) |
| is becoming(verb, expression, must, should, requires) |
| is fitting(verb, expression, must, should, requires) |
| is logical(verb, expression, must, should, requires) |
| is natural(verb, expression, must, should, requires) |
| is necessary(verb, expression, must, should, requires) |
| is reasonable(verb, expression, must, should, requires) |
| must(verb, should, behoves) |
| ought to(verb, expression, must, should) |
| requires(verb, must, should, behoves) |
| be duty-bound to(must, should) |
| be responsible for(verb, move, order, make, close) |
| find a way(verb, expression, force, show, drive) |
| go along with(verb, expression, force, show, drive) |
| guide physically(verb, expression, force, show, drive) |
| had better(expression, must, should) |
| have a duty to(expression, idiom, must, should) |
| lead |
| pass along(verb, expression, force, show, drive) |