Imperial units commonly used units for length are (li), (tseung/cheung), (tsek/chek), (tsun/chun), (fen/fan) in descending scale order. These units are now rarely used in daily life, the imperial and metric systems being preferred. The imperial equivalents are written with the same basic Chinese characters as the Chinese system. In order to distinguish between the units of the two systems, the units can be prefixed with "Ying" () for the Imperial system and "Wa" () for the Chinese system. In writing, derived characters are often used, with an additional (mouth) radical to the left of the original Chinese character, for writing imperial units.
Green imperial pigeon Indonesia. It has several subspecies, including the distinctive Celebes form, chestnut-naped imperial pigeon ("Ducula aenea paulina"). This is an arboreal dove, feeding on plant material in the tree canopy. Its flight is fast and direct, with the regular beats and an occasional sharp flick of the wings which are characteristic of pigeons in general. It builds a stick nest in a tree and lays a single white egg. The birds are not very gregarious, but will form small flocks. Green imperial pigeon The green imperial pigeon ("Ducula aenea") is a large forest pigeon. The green imperial pigeon is a large,