Evidence obtained from observation and experiment is often used to _____ a scientific theory.
Hurricane Sandy struck the northeastern United States, ____________ millions of people homeless.
-- Hi, Samantha! When did you arrive in Leeds? --- Last week, I ___________ a different culture since then.
Chengdu No. 7 High School, _____________ in 1905, is home to a great many excellent students.
The old man has two sons, __________ lives with him, so he has always felt lonely since his wife’s death.
No matter where he is, he makes ________ a rule to go for a walk before breakfast.