题干

 将“先”与“后”填入下列空格内。
(1)用盐酸中和氢氧化钠溶液时,____滴加几滴酚酞试液,____ 滴加盐酸。
(2)稀释浓硫酸时,向烧杯内____加水,____ 加浓硫酸。
(3)不慎将较多量浓碱溶液泼洒在实验台上,应该____用水冲洗,____ 用适量的稀醋酸中和。
(4)称取5gNaOH固体时,____向托盘上的表面皿内加NaOH固体,____ 向托盘内加砝码。

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先,后,先,后,后,先,后,先

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   My father had always been an alert observer of human character. Within seconds of meeting someone, he could sum up their strengths and weaknesses. It was always a challenge to see if any of my boyfriends could pass Dad's test. None did. Dad was always right—they didn't pass my test either. After Dad died, I wondered how I'd figure it out on my own.

   That's when Jack arrived on the scene. He was different from any other guy I'd dated. He could sit for hours on the piano bench with my mother, discussing some composers. My brother Rick loudly announced that Jack wasn't a turkey like the other guys I'd brought home. Jack passed my family's test. But what about Dad's?

Then came my mother's birthday. The day he was supposed to drive, I got a call. “Don't worry,” he said, “but I've been in an accident. I'm fine, but I need you to pick me up.”

    When I got there, we rushed to a flower shop for something for Mom. “How about gardenias(栀子花)?” Jack said, pointing at a beautiful white corsage (胸花). The florist put the corsage in a box.

The entire ride, Jack was unusually quiet. “Are you all right?” I asked. “I've been doing a lot of thinking,” he said. “I might be moving.” Moving? Then he added, “Moving in with you.” I nearly put the car on the sidewalk. “What?” I asked. “I think we should get married,” he said. He told me he'd planned his proposal in a fancy restaurant, but after the accident, he decided to do it right away. “Yes,” I whispered. We both sat dumbfounded, tears running down our cheeks. I'd never known such a tender moment. If only Dad were here to give his final approval.

  “Oh, let's just go inside.” Jack laughed. My mother opened the door. “Happy Birthday!” we shouted. Jack handed the box to her. She opened it up. Suddenly, her eyes were filled with tears. “Mom, what's wrong?” I asked. “I'm sorry,” she said, wiping her eyes. “This is only the second gardenia corsage I've ever received. I was given one years ago, long before you kids were born.” “From who?” I asked. “Your father,” Mom said. “He gave me one right before we were engaged.” My eyes locked on Jack's as I blinked away (眨掉) tears. Dad's test? I knew Jack had passed.