（１）They tried to climb the tree.
（２）They tried climbing the tree.
（３）I remember to post the letter.
（４）I remember posting the letter.
（５）He forgot to meet her.
（６）He forgot meeting her.
（７）We enjoyed singing all night.
（８）I finished reading the book.
（９）Mary wants to read the book.
（10）I am starting to feel sick.
（11）She started teaching English ten years ago.
（12）John decided to write a letter to Mary.
（13）He promised his mother not to go there alone.
（14）I hope to see you again.