Could you give me one more blanket?
请再给我一条毯子好吗?
One extra pillow, please.
请再给我一个枕头。
Can 代表一种能力时
I believe I can fly, I believe I can touch the sky. (R. Kelly的一首歌:I believe)
I can drink. 我能喝。
I can eat. 我能吃。
I could drink. 我之前很能喝。
I could eat. 我之前很能吃。