题干

用普通光学显微镜观察水中微生物,若发现视野中微生物往图1方向游走,请问你应该把载玻片往图2的哪个方向移动(    )

A:甲

B:乙

C:丙

D:丁

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答案(点此获取答案解析)

C

同类题4

阅读下面短文, 从短文后各题所给的四个选项(A、B、C、D)中, 选出可以填入空白处的最佳选项。

    My wife and I were attending a wedding at St. John's Church. The sound of 1rang to the heavens as the ceremony continued.

    At the church, I 2an old friend, Casper, who happened to be at the3. Now 73, Casper was a brilliant and 4softball pitcher(投球手)back in the Men's Leagues of Philadelphia in the mid-60s. I did not 5the now silver-haired fellow until my brother-in-law John mentioned his name to me!After a very pleasant 6, Casper asked if I remembered a letter of 7I had written to him back in 1964. It appeared Casper fell on hard times, as professional pitchers8do, and he wasn't pitching too well for a period of time. I did not 9the letter, but he said, “Yes, I still have it and I read it anytime 10aren't going too well.” He said that he had read the letter many times, and the situation always seemed to improve. I was 11and speechless!

    He continued, “You don't remember?” I said, “Sadly, no, I don't.” But I did ask if I could have a(n) 12of the letter. He said he would email it to me. After the 13, we met on the steps of the church. Casper came up to me and 14the letter. He lived a block from the 15 and had run home to get it. The envelope was 16 and turned yellow, and so was the letter inside. That letter had to be nearly 50 years old.

    In 17 terms, the letter read: “These hard times are 18!Keep your enthusiasm for the 19. Never quit and you'll be back on the top again 20. Hang on there!”