—What is behind the tree? —There must be a dog ______ there. [ ]A. to sit B.

题型：专项题难度：来源：

—What is behind the tree?
—There must be a dog ______ there. [ ]
A. to sit
B. sit
C. sitting

答案

举一反三

When he arrived at the office, he found all the workers ______. [ ]
A. working
B. work
C. to work
D. worked

题型：山东省中考真题难度：| 查看答案

Simon heard his neighour ______ for help at night. [ ]
A. calls
B. call
C. calling
D. to call

题型：期末题难度：| 查看答案

It"s cold here. Please keep the window ______. [ ]
A. close
B. closed
C. closing
D. closes

题型：期末题难度：| 查看答案

There _____ a few sheep _____ grass there. [ ]
A. are, eatting
B. is, eatting
C. are, eating
D. is, eating

题型：期末题难度：| 查看答案

I saw him ______ into the house when I walked past.

[ ]

A. to walk
B. walking
C. walked
D. walks

题型：江苏期末题难度：| 查看答案