I had to ______ because someone else wanted to use the phone.
—Where is Bob? I cannot find him anywhere. —Hehave been off long. I heard him make a call just now.
Class regulations require _____ is the last to leave the classroom _____ off all the lights.
What impresses me most is _________ he appears in front of others, he wears a sincere and charming smile. A. which B. that C. whereC. that whenever
Everyone has periods in their lives __________ everything seems very hard.
The result was far beyond _____we had expected, ____brought great joy to every one of us.