He was such __ good speaker that he held our attention every minute of __ three-hour lecture.

Obama delivered a speech to 500 local youths during his visitto China, many of were from Fudan Universityand Tongji University

To work at homehas been made _____ with the development of the Internet.

is the most widely used resource in ______industry, and plays ______ major role in energy production.

When I entered, I found my father ______ on the sofa and ______ in a magazine.