Question

Which of the following is a sentence fragment?

A. Hiding in the tree fort he had built as a kid.
B. Checking his mail each day was always fun.
C. Realizing you are getting older is sobering.
D. Knowing he would be late, she took a nap.

Answer 1

A. is the fragment. It has a gerund phrase but no actual verb that makes it a sentence. The other sentences do, however: was, is, and took.