计算：
(1)   $\left(-\frac{5}{6}\right)-\left(-1\frac{3}{4}\right)+\left(-1\frac{1}{6}\right)-\left(-\frac{1}{2}\right)$
(2)   $-7^2-\left(\frac{1}{2}-\frac{5}{6}-\frac{7}{12}\right)\times {\left(-\frac{1}{6}\right)}^{-2}$
(3)   $-3^3-\left|{\left(-5\right)}^3\right|\times {\left(-\frac{2}{5}\right)}^2-18+\left|-{\left(-4\right)}^2\right|$
(4)   $\frac{5}{7}\times \left\{\frac{7}{10}\times 2\times {\left(-1\right)}^3-3-10\frac{1}{2}\right\}-7\times \frac{3^2}{7}$

词形转换
There are some ____ at school. (boy)
 Is this ____ classroom? (we)
There are five____ in the room. (child)
 Are there ____ boats in the river? (some)
There are three____ and four __________ in the picture. (man, woman)
Mary, is this ____  bottle of coke? (you)
Daming ____ (be not) in Class Three.
I have two ____ (pencil-box)
Bill is from ____ . (American)
What are____ .(that)
Are you in ____  One? (grade)
There are two ____ on the wall. (picture)
Look! These____ are good. (cake)
Are these ____  apples? (you)
Lingling is from ____ . (Chinese)

如图是小明在体育考试中测试“引体向上”时的示意图，关于“引体向上”，下列说法中正确的是（　　）

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