請標出下列有機化合物的官能基並寫出其名字

請標出下列有機化合物的官能基並寫出其名字

1.............................O
.............................. ll
................CH3-CH2-C-H


2.........O
...........II
...CH3-C-O-CH2-CH2-CH3


3.....................CH3
..........................I
..............CH3-O-C-CH3
..........................I
.......................CH3


4........................OH
...........................I
..................CH3-CH-CH3



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