Common words:
* see
* me
* tree
* free
* bee
* feet
* sleep
* deep
* need
* green
Less common words:
* sheep
* cheek
* fleet
* keen
* freeze
* squeeze
* bleeding
* glee
Words with "ee" in other parts of the word:
* believe
* receive
* achieve
* piece
* brief
* chief
Note: Some words like "people" and "coffee" have the long E sound but are spelled differently.
This is just a small sample, there are many more words with the long E sound spelled "ee"!