【化】 polytrimethylene formal
assemble; gather
【建】 poly-
【化】 propilidene; propylidene
contract; crinkle; draw back; shrink; withdraw
formaldehyde
【化】 formaldehyde; methanal; methyl aldehyde; methylene oxide; oxymethylene
【医】 formaldehyde; formic aldehyde; methanal; methyl aldehyde