Complex sentence: Insulators and semiconductors differ from metals and semimetals in that the electrical conductivity of an insulator or semiconductor increases with temperature rather than decreases like that of a metal or semimetal.
Split into simpler sentences: Insulators and semiconductors differ from metals and semimetals in the temperature dependency to their electrical conductivity. With an insulator or semiconductor, the conductivity increases with increases in temperature rather than decreases like that of a metal or semimetal.