_________do you write a letter to your father— I seldom or never do that now. Instead, I call or e-mail him almost every day.

rus Ebola is reported ______ over 3,000 lives in 5 countries of West Africa by now.

Do you know if Dr White will come for dinner this eveningNo, but I think he ______ if he ______busy.

We shouldn’t________he trees in order to protect the environment．

ou meet some trouble about how to usethis new kind of machine, you canthe instruction.