human experiment; human experimentation; experiment on a living person
infancy; childhood; tender age
infiltration; sneaking in; going undercover
residence; housing; residential building
lightly and smoothly (of movements); swiftly; glidingly; (progressing) smoothly; (solving) easily
six; six years of age; six o'clock (old time system)
suspicious; dubious; unreliable; indecent; unseemly
field; sphere; realm; division; branch
tenant (esp. of an apartment); occupant; resident (e.g. of a nursing home)
coat; jacket; outerwear; top; upper-body garment
layering (clothing); wearing one garment over another
jacket; book jacket; dust cover; CD jacket; record jacket
the country; countryside; rural districts; cultivated land; fields
fossil; petrifaction; petrification; fossilization
along (a river, coast, railway, etc.); on (e.g. a street)
dividing into four; quartering
to change; to switch; to change over (to); to renew
at full speed; as fast as one's legs can carry one
to be shut; to close; to be locked; to tighten; to be tightened; to become sober
pocket heater; hand warmer; heater pack
stopping position (of a vehicle; at a pedestrian crossing, traffic lights, etc.)
about the same; about equal to; close match
slapping the opponent with the open hand
joint; link; knot; tie-together point
to cut open; to clear (land); to cut (a path, road, etc.); to carve out (a new career, future, etc.); to open up (a new field)
byway; bypath; byroad; loophole; way out (of trouble); excuse
person concerned; people involved (in an event); those concerned; staff
branch; branch office; subdivision
to throw oneself (e.g. off a cliff, etc.)
practice by repetition; learning by rote
dotted line; perforated line
to understand; to be convinced; to be satisfied
bur (of a chestnut, etc.); burr; irritating (e.g. one's throat); thorny; (arch.) crying of a baby
pressing; urging; demanding; demand
to reflect on (oneself, past conduct, etc.); to contemplate; to examine; to think over; to introspect