Something like this maybe?
Code:
while(1) {
    int i;
		
    for (i = 0; i < 10; i++) {
        draw_line(vector(20+20*i,10,0), NULL, 100);
        draw_line(vector(20+20*i,200,0), vector(0,0,255), 100);
    }
		
    wait(1);
}