Q:

"You can not bathe in this sea, "he said to me, "It's very rough."

• 1
  He said that I cannot bathe in this sea because it's very rought.
• 2
  He said that you could not bathe in the sea if it was very rough.
• 3
  He said that I could not bathe in that sea as it was very rough.
• 4
  He said that you can not bathe in this sea since it was very rough.