correct form of verb

[akbar]

Thank you very much for each answer.
Now I seek another help. Please check the given verbs in brackets.Are they correct or not?
The last wonder of the modern world (will be) simply that we( will have been )still here. We (will have) bombs that (can )destroy the world but we (do not use) them. This (would be )surely the greatest wonder of all!

[Casiopea]

Good try. Please check the underlined phrases:

The last wonder of the modern world (will be) simply that we (will have been )still here. We (will have) bombs that (can) destroy the world but we (do not use) them. This (would be) surely the greatest wonder of all!