【题目】Only when you become a parent, ___________understand your mother.

【题目】— I never expected the experiment would be ________ failure.

【题目】The only problem was ______ we kept getting lost! But people in Tianjin were very friendly and helpful.

【题目】____ I look back to those days as a child, I really hope to spare more time to accompany my father.

【题目】The man caught hold of the side of the lifeboat and narrowly escaped______.

【题目】We should improve our ability to engage in international communication so as to tell China’s story well and make the voice of China ______.

【题目】_____ is known to us that the Amber Room belongs to the Russians.

【题目】He bought a new building _____top is different from those of the others around.

【题目】Usually there might be a lot of accidents in the heavy fog. I happened to witness _______ this morning.

【题目】The other day, my brother drove his car down the street at _____ was a dangerous speed.