fixed task; scheduled task
weather resistance (e.g. in building material)
ionization tendency; ionisation tendency
lecture fee; teaching fee
sulphurous acid gas; sulfurous acid gas; sulphur dioxide gas; sulfur dioxide gas
as is usual with; in common with
sulfanilamide; sulphanilamide
the three Rs; reading, writing and arithmetic
language study; language learning
sodium bicarbonate (NaHCO3)
to talk casually; to use one's peer language (to others)
samurai drill; knight errantry
isolation (e.g. of a particular chemical substance within a mixture)
silicon dioxide (SiO2); silica
seal over the edges of adjacent sheets; tally impression