Have you got John’s letter—Yes, but I don’t think his letter is worth _______.

driving, which was once a occurrence,is now under control七彩教育网

Where is Lily, Lucy? I cannot find her anywhere. — She _____have been off long. I saw her clean the window just now. [ ]

It’s quite warm here; we __________turn the heating on yet.

Part of the reason Charles Dickens loved his own novel, David Copperfield, was ________ it was rather closely modeled on his own life.(2010·北京)