Mr. Brown didn’t believe that such a little thing could _____ much.
| A．mind | B．matter | C．trouble | D．happen |
32. Tens of thousands of trees _____ in the area in the past few years.
| A．have been planted | B．were planted | C．have planted | D．had planted |
31. — I'm wondering why the visitors chose to stay with the host family.
— _____real local life.
| A．Experiencing | B．Experience | C．To experience | D．Having experienced |
30. How long do you think it will be _____ we can find a new water source?
| A．after | B．before | C．when | D．Since |
29. High up in the mountains _____ a quiet small village, with only 20 households.
| A．surrounds | B．locates | C．lies | D．Lays |
28. A heavy snow promises a good harvest, _____ is often the case.
| A．where | B．as | C．that | D．What |