穿梭

穿梭	chuān suō	to shuttle back and forth
穿	chuān	to bore through; to pierce; to perforate / to go through (e.g. a tunnel); to cross (e.g. a street) / to thread; to string together / to wear; to put on (clothes, shoes etc.) / verb complement indicating thoroughness or completion
梭	suō	(textiles) shuttle