. A variety of courses ________ offered to enrich the students’ background knowledge of the English-speaking countries.
I haven't seen her ____ the past few years.
What have you done ____ my picture-book?
.---Do you like working as a waiter? -----Yes, but I get tired ___ the whole day.
I saw a man standing ___ the tree ___ a distance of twenty yards.
---Please come here again. -----I will surely ____ you when I come to your city someday.