— Did you remember to give Jack the book?
—Yes, I gave it to him ______ I saw him.
| A．while | B．immediately |
| C．once | D．suddenly |
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 |
— 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 |
How long do you think it will be _____ we can find a new water source?
| A．after | B．before | C．when | D．since |
High up in the mountains _____ a quiet small village, with only 20 households.
| A．surrounds | B．locates | C．lies | D．lays |
A heavy snow promises a good harvest, _____ is often the case.
| A．where | B．as | C．that | D．what |