Present Perfect Passive

1) Some new cars ___ been sold this week.

2) This room hasn't been ____ (use) for ages.

3) A new school has ____ ( build) in our city this summer.

4) Many important problems have____ ( discuss) already.

5) The huge shopping center __ been opened recently.

6) This tasty cake has been cooked ___ Helen.

7) The article has been written __ the editor.

8) These drawings have been made ___ pencils.

9) You ____ ( warn)!

10) They ____ (not, see) since then.