A:I’m glad you like it.
B:Then I’ll give you a better one next time.
C:You have a gift for present
D:I’m sorry I can’t make you satisfied
比较“商品—商品”和“商品—货币—商品”这两种交换方式,不难看出前者更加便捷。( )
No one was allowed to leave the lab without the professor's p____.
现存生物中,许多简单、低等的生物并没有在进化过程中灭绝,是因为这些生物能( )
There _____ many watermelons in the shop.