To make a bamboo chair, people cut the bamboo half, put the skin of other side on fire to heat it up,
the bamboo skin becomes soft, and easily being bent before it is cool down.
The wood could be bent too, people make the same type of chairs from wood tree.
The big seal script of the character Bent is
Very similar to the shell bone script.
The small script of the character is
The clerical script of the character is
the top and middle lines are connected. It is easier to right, but the pictography is gone, which is the major trend in the Chinese evolution: To make the writing easier but lose the pictography.
Its Pinyin is Qu1.
The character 曲 also means song, and music now but the pronunciation become Qu3. I have not found a very good explanation why it could mean song and music.