criterion;  standard;  yardstick;  rough estimate;  approximation
 time;  hour;  period;  class
 now;  soon;  already;  yet;  further;  more
 to go to bed;  to be sick in bed;  to be laid up
 to feel (as if);  to have a feeling (that);  to have a hunch (that);  to feel like doing;  to want to do
 going to bed;  retiring (for the night)
 to talk;  to tell;  to recite;  to pledge;  to conspire with
 custom;  general rule;  convention;  usually;  generally;  as a rule
 thin;  skinny;  delicate;  fragile;  feeble
 only;  just;  merely;  as much as;  to the extent of;  enough to
 sleepiness;  drowsiness;  the sandman;  Morpheus
 to gulp down;  to swallow deeply;  to understand;  to take in;  to engulf;  to swallow up
 right;  correct;  proper;  righteous;  just
 (approximate) time;  around;  suitable time (or condition);  time of year;  season
 hygienic;  healthy;  healthful;  sanitary
 but;  however;  provided that
 24 hours;  twenty-four hours
 guarantee;  security;  assurance;  pledge;  warranty
 actually;  really;  truly;  in practice;  practically
 to hit;  to expose;  to apply (e.g. patch);  to put on;  to allot;  to call on someone (e.g. in class);  to guess (an answer)
 may;  might;  perhaps;  may be;  possibly
 clear;  distinct;  evident;  definite
 accurate;  correct;  precise;  exact
 numeral;  figure;  digit;  numeric character
 to understand;  to comprehend;  to become clear;  to be known;  I know!;  I think so too!
 change;  alteration;  difference;  distinction;  something wrong;  abnormality
 intensely;  severely;  strictly;  tightly;  compactly;  closely
 cooking;  cookery;  cuisine;  dealing with something;  handling;  administration
 full stomach;  bellyful;  (eat) heartily;  to one's heart's content
 to eat;  to live on (e.g. a salary);  to live off;  to subsist on
 soundly (sleeping);  fast (asleep)
 sleep;  sleeping;  inactivity;  death
 you have only to;  all you have to (do);  all that's required;  as long as;  if only
 fatigue;  weariness;  exhaustion;  tiredness
 lively;  full of spirit;  energetic;  healthy;  well;  fit
 so;  like this;  in this way