please correct the following sentences so they read clean and clear.

1. It is David Lurie's eros that troubles the college administrators.
2. It is strongly requested that all pedestrians refrain from walking over those areas in the park which have been planted in grass.
3. In my opinion, I think that students should be allowed to write any paper or essay which they feel like writing, regardless of what the requirements given by the professor are.
4. You should rest at any point in time that you feel drowsy.
5. A few wise smokers eventually kick the habit, but some never smarten up. Oh well.
6. The lofty reaches of the craggy tops of the mountains were covered by the freezing precipitation that fell in a frenzied swirl.
7. Walking through the streets of Konigsberg, the categorical imperative came up in the mind of Kant.
8. For sale: an antique desk suitable for a lady with thick legs and large drawers.
9. At MacDonald's, the fullback was like a bulldozer wolfing Big Mac's like they were whales.
10. After losing her heart to him, Gurov takes advantage of Anna's naivety.
11. To end the war in Iraq now is more problematical than continuing it.
12. Elmo plays that song much better on the kazoo.

my attempt: Can you check over my work.
1. It is David Lurie's errors that trouble the college administrators.
2. It is urgently requested that all pedestrians refrain from walking over those areas in the park where grass has been planted.
3. In my opinion, students should be allowed to write any paper or essay they feel like writing, regardless of what requirements the professor sets.
4. You should rest at any point in time at which you feel drowsy.
5. not sure how to fix
6. The lofty reaches of the craggy mountain tops were covered by freezing precipitation that fell in a frenzied swirl.
7. The categorical imperative came to Kant's mind while he walked the streets of Königsberg.
8. For sale: an antique desk with large drawers. suitable for a lady with thick legs.
9. At McDonald's, the fullback wolfed down Big Macs like a whale.
10. After Anna loses her heart to him, Gurov takes advantage of her naïveté.
11. It would now be more problematic to end the war in Iraq than to continue it.
12. not sure how to fix.

4. You should rest at any point in time at which you feel drowsy.
I would suggest. It is important to rest when one is drowsy.
5. A few wise smokers eventually kick the habit, but many are never able to accomplish this.
8. For sale: an antique desk with large drawers and thick legs, suitable for a lady .
9. At MacDonald's, the fullback was like a bulldozer plowing through Big Mac's .
11. There would now be more problems ending the Iraq war than in continuing it.

do u know how i should correct 12.

12 is fine...doesn't need correction.

The only thing I would do with #12 is to add a "than..." phrase.

Elmo plays that song much better on the kazoo than on the flute.

... to complete the comparison.

=)

Good job with your corrections! Here are a few suggestions to further improve the sentences:

5. A few wise smokers eventually kick the habit, but many are never able to quit.
12. Elmo plays that song much better on the kazoo than he does on the flute.

In sentence 5, "smarten up" is replaced with "quit" to make the sentence clearer.

In sentence 12, "better" is followed by "he does" to complete the comparison.