问题
选择题
下列计算中，正确的是（ ）
|
答案
A、2
+2
不是同类二次根式，所以无法计算，错误；3
B、3
×23
=62
正确；6
C、-
=3错误，应等于-3；(-3)2
D、
-8
=2
应等于6
．故选B．2
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下列计算中，正确的是（ ）
|
A、2
+2
不是同类二次根式，所以无法计算，错误；3
B、3
×23
=62
正确；6
C、-
=3错误，应等于-3；(-3)2
D、
-8
=2
应等于6
．故选B．2
| 完形填空。 | ||||
| Laura lived in a small villager near the sea. One day she wanted to go 1 a swim in the sea. She knew that the sea had a strong tide (潮水), but she was a good swimmer, so she wasn't 2 . While Laura's friends were lying on the sands, she ran into the sea. She swam quite 3 from the beach and waved (挥手) to her friends in the distance (远处). After a short while she wanted to swim back. She tried her best, but she couldn't get any closer to 4 . The tide kept pushing (推) her back. She waved her arms to let her friends 5 that she was in trouble, but they just waved back, for they didn't know what she 6 . After a long time, Laura became very 7 and she couldn't swim any more. Her legs went down 8 she lost hope. Suddenly, her foot touched the sand. All the time she was in a place and there the water 9 deep (深的). When at last she went back to the beach, one of her friends asked, "Did you enjoy your swim?" "Yes, it was lovely," she answered. Laura never told her friends what really 10 to her on that day. | ||||
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