With the development of modern agriculture and industry, ____ waste are created every day.
| A．a large quantity of | B．large quantities of |
| C．a large number of | D．large numbers of |
His letter was so confusing that I could hardly make any ______ of it.
| A．explanation | B．meaning | C．sense | D．guess |
Today the canal is still being used. Ships can be seen moving on ______ water now and then. But it is no longer ______ busy water highway.
| A．a, the | B．the, / | C．/, a | D．the, a |
Is this the reason ________ at the meeting for his carelessness in his work?
| A．explained | B．what he explained |
| C．how he explained | D．why he explained |
If I ________ you，I ________ more attention to English idioms and phrases.
| A．was; shall pay | B．am; will pay |
| C．would be; would pay | D．were; would pay |
Come to pick me up if _______
| A． you are convenient | B．at your convenience |
| C． it is convenient | D．for convenience |