This factory produced much dirty water, which resulted in a wide______of environmental problems．
| A．branch | B．range |
| C．species | D．wave |
Mom used only half of the money, the rest of which ______ saved for other purposes.
| A．is | B．are | C．was | D．were |
As he reached _____ back door, Jack saw _____ strange sight.
| A．the ; / | B．a; the | C．/; a | D．the ; a |
Between the two parts of the concert is an interval, ______ the audience can buy ice-cream.
| A．when | B．where | C．that | D．which |
––Linda didn’t invite us to the party.
–– ______? I don’t care.
| A．For what | B．So what | C．What’s on | D．What’s up |
---It’s a long time since I saw my sister.
--- ______her this weekend?
Why not visit B. Why not to visit
C. Why not visiting D. Why don’t visit