A:肯定大于15mL
B:肯定小于15mL
C:肯定等于15mL
D:可能大于也可能小于15mL
下列说法中,正确的是( )
A: What can you ____?
B: I can see two ____.
A: What ____ ____ they?
B: They are ____ and ____. (黑色和黄色)