There＿＿＿so many careless mistakes in his writing, Tom was told to write another passage carefully.
| A．to be | B．were |
| C．had been | D．being |
________ it rain tomorrow, we should have to put off the visit to the Yangpu Bridge.
| A．Were | B．Should |
| C．Would | D．Will |
If we had taken such effective measures much earlier, the river ________ so seriously now.
| A．is not polluted |
| B．would not be polluted |
| C．had not been polluted |
| D．would not have been polluted |
George is going to talk about the geography of his country, but I'd rather he ________ more on its culture.
| A．focus | B．focused |
| C．would focus | D．had focused |
Don't handle the vase as if it ________ made of steel.
| A．is | B．were |
| C．has been | D．had been |
Jack is a great talker. It's high time that he ________ something instead of just talking.
| A．will do | B．has done |
| C．do | D．did |