Suppose someone gave you a pen — a sealed, solid-colored pen.You couldn’t see how much ink it had.假设有人给了你一枝笔，一枝密封的、纯色的水

Suppose someone gave you a pen — a sealed, solid-colored pen.You couldn’t see how much ink it had.假设有人给了你一枝笔，一枝密封的、纯色的水