—The state of illness is complicated．We need an experienced doctor．—Whom would you like to have____?

The meeting ________ now is of great importance.

Many developed countries have agreed to help the less developed ones but it remains ________ whether they will take action or not.

 ________ on the endless green grass are sheep, cattle and horses.

     necessary experience for my future career, I take an active part in social activities in college.