In a conference call with state and local officials Wednesday afternoon, Mr. Obama __________confidence in the procedures(程序) already in place to prevent the spread of Ebola(埃博拉病毒)

terrible experience! ________, you’re safe now—— that’s the main thing.

Would you be ___ to help me with my study?—I’ll be very glad ___ it.

______________________________ —I live in a farmhouse with my family.

In the past twenty years great changes _______in China