<def-root>A particular <fen>State_of_affairs</fen> is desirable. The <fen>State_of_affairs</fen> may be required to achieve a <fen>Purpose</fen>. A set of <fen>Circumstances</fen> may be specified under which the assessment of desirability holds.
<ex><fex name="sta">You</fex> <t>should</t> <fex name="sta">take the doses about 12 hours apart and at the same time each day</fex>.</ex>
<ex> <fex name="cir">If the metal is seriously rusted or warped</fex>, <fex name="sta">it</fex> <t>should</t> <fex name="sta">be repaired or replaced with a chimney top damper</fex>.</ex>
<ex><fex name="pur">To ensure that</fex>, <fex name="sta">you</fex> <t>should</t> <fex name="sta">have no CLASSPATH set</fex>.</ex></def-root>
<def-root>The <fen>State_of_affairs</fen> that the speaker finds desirable.</def-root>
<def-root>The FE <fen>Circumstances</fen> encodes a setting, often temporal or spatial, within which the <fen>State_of_affairs</fen> has the specified assessment of desirability.</def-root>
<def-root>The event or state of affairs that is achieved by bringing about the desirable <fen>State_of_affairs</fen>.</def-root>
<def-root>The extent to which the specified desirability of the <fen>State_of_affairs</fen> deviates from the expected desirability.</def-root>
Desirability
Preferred_alternative_scenario
Required_event
Taking_sides
FN: have an obligation to
FN: have an obligation to
FN: be an undesirable course of action
FN: be a desirable course of action
FN: must
COD: be required or expected to do something.