observation; survey; watching
to carry (something) under cover; to carry concealed
hypothesis; supposition; assumption; expectation; anticipation
gazing steadily at; observing (a person) closely; maintain a watch over
genuine; authentic; true; real
testimony; (verbal) evidence
to grow; to grow up; to be good at; to excel in
old manners; old style; old school (of art)
profound; deep; deep (of a cave, etc.); innermost; interior
point of view; viewpoint; standpoint; field inspection (e.g. in architecture, building)
to present; to offer; to show; to display; to assume (e.g. a shape)
hard; solid; stiff; tight; strong; firm (not viscous or easily moved); safe
astonishment; amazement; surprise; fright; shock
oscillation; vibration; swing (e.g. of a pendulum)
to fall (over, down); to collapse; to be destroyed (in a collapse); to collapse; to be confined to bed (with an illness); to come down with; to die
to get drunk; to become intoxicated; to feel sick (e.g. in a vehicle); to become nauseated; to be elated; to be exalted
bothersome; tiresome; bother to do
sound wave; acoustic wave
side effect; adverse reaction
illusion; hallucination; misapprehension; misconception; misunderstanding
burn; scald; (fig.) getting one's fingers burned (e.g. poor investment, mixing with the wrong people)
hint; suggestion; clue; suggestion
on a routine basis; regularly; habitually
how; in what way; by what means
wise; sagacious; intelligent; sensible
end; ending; close; end of (one's) life; death
to be piled up; to lie on top of one another; to come one after another; to happen over and over; to overlap (each other); to occur at the same time
choppy sea; chopping waves; triangle wave
seeing for the first time; first sight; first meeting; sight-reading
point of uncertainty; unclarified issue; doubt
processing speed; handling speed
to be called ...; to be referred to as ...
silver; senior citizen; pensioner
riddle; puzzle; enigma; enigmatic; mysterious
genius; prodigy; natural gift