下列x的值能使 $\sqrt{x-6}$有意义的是（　　）

    Someone had given our name and phone number to a charity, and its staff were bringing us Christmas presents.

    I made sure the house was as spotless as it could be with four children living in it, as the due time drew near, I sat on the edge of the couch. Each time I heard a car, I jumped up to see if they were here. Each time it wasn't them, I was relieved, yet disappointed.

    Finally a huge car pulled into the driveway, and four people got out. Now I was embarrassed as well as grateful, excited and nervous. I greeted them with a smile. They made several trips and soon my living room was full of boxes and bags.

    I tried to say “thank you” but my throat suddenly closed up and tears welled up in my eyes.

    I watched through the window as they drove away, wondering what they thought of me. I had always donated, but not received. We weren't always like this. My husband had been out of work, and we were struggling. I'd wanted to say this to them, but the words wouldn't come out.

    I quickly put away the gifts before the school-aged children came home. I hid them in closets and under beds as quickly as I could. On Christmas morning I felt a little guilty as our four children tore open the boxes and bags with pleasure, thinking they were from us.

    My nine-year-old son opened a game box and taped inside the lid was an envelope. I opened it and read aloud: May the joy of Christmas be with you all through the year. At the bottom of the card, written in small, neat letters was a sentence, it said: Although the sea gets rough, no storm lasts forever.

    I was suddenly ashamed of being ashamed. I finally understood.