Trough : a long, narrow open container for animals to eat or drink out of
Fence : a barrier, railing, or other upright structure, typically of wood or wire, enclosing an area of ground to mark a boundary, control access, or prevent escape.
Whistle : a clear, high-pitched sound made by forcing breath through a small hole between partly closed lips, or between one's teeth.
Sound : vibrations that travel through the air or another medium and can be heard when they reach a person's or animal's ear
Corner : a place or angle where two or more sides or edges meet
Thought : an idea or opinion produced by thinking, or occurring suddenly in the mind