—This returned Chinese scholar has become one of the top experts in this field .

    —Yes , I know him very well . He  ____in Africa with wild animals for eight years .

   A．has worked         B．had worked       C．worked     D．has been working

----This returned Chinese scholar has become one of the top experts in this field.

----Yes,I know him very well.He____in Africa with animals for eight years.

A、has worke B、had worked C、worked D、has been working

—This returned Chinese scholar has become one of the top experts in this field .

—Yes , I know him very well . He         in Africa with wild animals for eight years .

A．has worked                B．had worked         C．worked               D．has been working

—This returned Chinese scholar has become one of the top experts in this field.

    —Yes , I know him very well. He ___________ in Africa with wild animals for eight years.

A.has worked           B.had worked        C.worked                   D.has been working

---This returned Chinese scholar has become one of the top experts in this field.

---Yes , I know him very well. He ______ in Africa with wild animals for eight years.

1. A.
   has worked
2. B.
   had worked
3. C.
   worked
4. D.
   has been working

---This returned Chinese scholar has become one of the top experts in this field.
---Yes,I know him very well.He______in Africa with animals for eight years.

1. A.
   has worke
2. B.
   had worked
3. C.
   worked
4. D.
   has been working

—This returned Chinese scholar has become one of the top experts in this field .

    —Yes , I know him very well . He         in Africa with wild animals for eight years .

   A．has worked       B．had worked     C．worked    D．has been working

----This returned Chinese scholar has become one of the top experts in this field.

----Yes,I know him very well.He_________in Africa with animals for eight years.

A、has worked    B、had worked    C、worked     D、has been working

--- This returned Chinese scholar has become one of the top experts in this field.

   --- Yes, I know him very well. He_________in Africa on wild animals for eight years.

  A.has worked                    B.had worked   

C.worked                        D.has been working