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補足: Is it new information or old?
Ouch! I've cut my finger!
Because this action has only just happened.
new == the fact is still alive
- Somebody has stolen my bicycle! Now I'll have to walk home.
- I've lost my keys! Now I can't get home.
- She has gone to America. Now you can't see her.
Because it is affecting the present(the fact is still alive).
応用編: thatと一緒に使うとき
I heard that she would release a new album.
she would release a new albumに焦点が当たっている。
なのでSo I will make a reservation tonight.などのつながりが生じそう。
またwillがbackshiftingしてwouldになっている（これはどうも必須ではないらしい）。
I have heard that she will release a new album.
heardしたこと自体に焦点が当たっている。
なのでHave you?など、heardしたこと自体に付随するつながりが生じそう。