It __________ be the vocabulary that caused you the problem in the exercise because you know a lot of words.
Scientists say they have found a way to produce the human body’s own cancer-killing cells through gene treatment, ______ new hope to cancer sufferers.
---- If it hadn’t been raining so hard, I might have been home much earlier. ---- It’s too bad you _____ it. Nancy _____ here and she _____ to see you.
The prices are _____ fast these days. Nobody can get the prices _____.
---- How does your second-hand car run? ---- It _____ run all right, but it is being repaired.
I _____ my son _____ a doctor, but he wasn’t good enough at science.