A few more from the top of my memory.
1. With pointed fangs I sit in wait,
With piercing force I dole out fate,
Over bloodless victims proclaiming my might,
Permanently joining by my single bite.
What am I?
2. The higher I climb, the hotter I engage, I can not escape my crystal cage.
What am I?
3. Once I was with water, full of scaly fish;
but by a new decision, Fate has changed my nature:
having suffered fiery pangs,
I now gleam white, like ashes or bright snow.
4. Without tiring it toils,
carrying loads across the muddy earth.
But despite of many things it can do,
it cannot be forced to return to the place of its birth.
5. I am just two and two. I am hot. I am cold.
I am the parent of numbers that cannot be told.
I am a gift beyond measure, a matter of course.
I am given with pleasure, or taken by force.
What am I?
6. Many keys I have but usually only three locks. What am I?
7. This old one runs forever, but never moves at all. He has not lungs nor throat, but still a mighty roaring call. What is it?