Pronounced as one letter, And written with three, Two letters there are, And two only in me. I’m double, I’m single, I’m black, blue, and gray, I’m read from both ends, And the same either way. What am I?

I sometimes clink, I hold with care, and carry your food unless you share. I’m happy to serve, but don’t you drop me, or I might just shatter with a sad little sound!

I fly up high with my little eye. For the sky, I am quite the reacher. But I can cause you to let out a sigh when I'm done by a boring teacher.

If you love me, avoid bottles and gifts of fire.

A measuring cup, piano, and most fish have this in common.