一个是介词词组，一个是相当于连词，下面有些例子希望对你有帮助，特别看倒数的三四个，你就会明白了。
instead of是介词短语,意思是"代替"、"而不",但在实际应用中它常常起着连接词的作用,在句中连接前后两部分平行对称的名词、形容词、副词、代词、动名词、不定式、介词短语、从句等。下面通过例句分类说明。
1. 连接两个名词
Shall we have fish instead of meat today? 我们今天吃鱼不吃肉,好吗?
2. 连接两个代词
Give me this instead of that. 给我这个,不要那个。
Give me the red one instead of the green one. 给我那个红色的,不要绿色的。
3. 连接两个形容词
He felt proud instead of ashamed of it. 他对此事感到骄傲而不是惭愧。
This is dull instead of interesting. 这不但没有趣,反而很枯燥的。
4. 连接两个形容词比较级
Things are getting worse instead of better. 情况变得越来越糟糕,而不是越来越好。
When water freezes, it becomes larger instead of smaller in volume. 水结冰时,其体积是变大而不是变小。
5. 连接两个副词
You should be out instead of in on such a fine day. 天气这么好,你应该出去走走,不要呆在家里。
He is walking quickly instead of slowly. 他走得很快,而不是很慢。
6. 连接两个介词短语
They went there on foot instead of by bus. 他们没有坐公共汽车而是步行到那里去。
We will have tea in the garden instead of in the house. 我们将在花园里而不是在房间里喝茶。
7. 连接两个谓语动词
On freezing water expands instead of contracts. 水在结冰时要膨胀而不是收缩。
That increased instead of decreased our anxiety. 那不但没有减少反而增加了我们的忧虑。
8. 连接两个动名词
She prefers making her own clothes instead of
buying them in the shops. 她宁可自己缝制衣服而不愿到服装店去买。
9. 连接两个带to的动词不定式
He wants to see the film instead of to play football. 他想看电影,不想踢足球。
He proposes to do some work instead of to watch television. 他建议去做点事而不是看电视。
10. 连接两个不带to的动词不定式
A word of encouragement might have made me
respect instead of hate him. 一句鼓励的话本来可以使我尊敬他而不讨厌他。
11. 连接两个从句
I told him about it as he was at home instead of as he was in the office. 我是在家里而不是在办公室把这件事告诉他的。