—Kathy and her sister are so alike.—I can’t tell one from ____.
30. With little knowledge about the area he succeeded ______ many researchers failed.
29. A very beautiful scene spreads in front of the mountain, at the foot of which ______.
28. What was unexpected was that the disrespectable fellow ______ the old man.
27. I wonder whether the police ______ that lost child or not
26. Jerry, why ______ you leave your things on the floor like this?