Combine these pairs of sentences, using a relative pronoun. Put comma(s) where necessary.
1/ Is that the room? You intended to put the piano in it
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2/ Mrs.Lan was very gentle. I picked up her umbrella accidentally
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3/ We have not decide the day. We'll go to London then.
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4/ These tubes need soldering at once. They have leaks
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5/ My youngest sister has just got married. You met her at my home last week.
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