Prodag
半胶态石墨悬浮液
🗣️ 情景例句
Fine. How much would you like to exchange, sir?
好的。您要兑换多少呢，先生？
Why tell you?
没必要对你说。
These are partly a matter of personal circumstances, partly a matter of psychology.
这里一方面是个人所处的环境，另一方面是个心理学的问题。