Theres nothing as secure, Thanga said, adding that it serves as an insurance policy in the event of global catastrophe. But I think the same complexity is what makes them beautiful, he said. Infrasound, also known as low-frequency sound, describes sound waves with a frequency below the lower limit of human audibility. Its not crazy big, Thanga insisted. It covers sounds below 20 Hz and down as far as 0.001 Hz.
never heard about global warming.
( z0 hear :ARG1 ( z1 warm :ARG1 ( z2 globe ) ) :polarity - :time ( z3 ever ) )
(z0 / hear-01
    :ARG1 (z1 / warm-01
              :ARG1 (z2 / globe))
    :polarity -
    :time (z3 / ever))
never heard about global warming .
z0 :polarity 0
z0 :time z3
z1 :ARG1 z2
z0 :ARG1 z1