81.   Plastic tubes connected to gas cylinders led to each room where the windows were tightly sealed.

82.   The calf cells were packed into small plastic tubes containing tiny pores that were big enought to let painkilling substances called enkephalins and endorphins leak out.

a. + tube >>共 340
feeding 9.22%
plastic 7.06%
breathing 6.98%
feed 4.05%
intravenous 3.96%
fluorescent 3.01%
metal 2.84%
thin 2.50%
tiny 2.24%
small 2.15%
plastic + n. >>共 1296
bag 17.24%
wrap 5.70%
sheeting 3.48%
container 3.05%
bottle 2.62%
bullet 2.33%
sheet 2.26%
cup 1.83%
chair 1.38%
box 0.98%
tube 0.92%
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