import turtle

def draw_square(t, size, color="black", fill=""):
    t.color(color, fill)
    if fill:
        t.begin_fill()
    for _ in range(4):
        t.forward(size)
        t.right(90)
    if fill:
        t.end_fill()

def draw_rectangle(t, width, height, color="black", fill=""):
    t.color(color, fill)
    if fill:
        t.begin_fill()
    for _ in range(2):
        t.forward(width)
        t.right(90)
        t.forward(height)
        t.right(90)
    if fill:
        t.end_fill()

def draw_triangle(t, size, color="black", fill=""):
    t.color(color, fill)
    if fill:
        t.begin_fill()
    for _ in range(3):
        t.forward(size)
        t.left(120)
    if fill:
        t.end_fill()

def draw_circle(t, radius, color="black", fill=""):
    t.color(color, fill)
    if fill:
        t.begin_fill()
    t.circle(radius)
    if fill:
        t.end_fill()