to study (in depth); to learn; to take lessons in
economy; economics; finance; (one's) finances; being economical; economy
heavenly body; celestial body; astronomical object
laws of nature; physical laws; physics
to be helpful; to be useful
of no use whatsoever; good for nothing; useless
high; tall; expensive; high-priced; high (level); above average (in degree, quality, etc.)
low (rank, degree, value, content, quality, etc.); low (position); close to the ground; short (height); deep (voice); in a low key
very interesting; of great interest
plausible; believable; solemn; dignified; serious
required subject; compulsory course
companion; partner; other party; addressee; opponent (sports, etc.)
indicates reason or excuse; indicates dissatisfaction; indicates desire to be pampered or indulged
being in charge (of an area of responsibility); being responsible (for a work role, etc.)
professor; teaching; instruction
unthinkable; unexpected; absolutely not!; far from it!; (it was) no bother at all; not at all
to be attached; to be connected with; to remain imprinted; to scar; to bear (fruit, interest, etc.); to be acquired (of a habit, ability, etc.); to increase (of strength, etc.)
speech; expression; wording; language
to match (rhythm, speed, etc.); to join together; to unite; to face; to be opposite (someone); to compare; to check with
that's the way it is; yes; is that so?; is it?
imagination; supposition; guess
most suitable; optimum; optimal; best
ten thousand years; eternity; perennial; perpetual
cause; seed; variety; kind; counter for varieties
disagreeable; detestable; unpleasant; reluctant
to knit one's brows (in discomfort, unease, disapproval, etc.); to raise one's eyebrows; to frown; to scowl
to spit out; to eject; to dump
century; hundred years; (fig.) a long time
have no choice; there is nothing but; no more than
person's origin (e.g. city, country, parentage, school)
valuation; appraisal; evaluation; appreciation; recognition; acknowledgement
not less than; ... and over; beyond (e.g. one's expectations); above; above-mentioned; aforementioned
disagreeableness; unpleasantness; nastiness; cutting remark; disagreeable remark; snide comment
opening fully; full throttle; full power
murmur; mutter; murmuring; tweet; Twitter post
unskillful; poor; awkward; imprudent; untactful
may; might; perhaps; may be; possibly