The word quicksand (流沙) makes some people shake with fear. This is probably because of the way many movies show it. In those ____1____ (film), quicksand often suck (吸) people and animals to their deaths!

Real quicksand is not the same ____2___ movie quicksand. It usually doesn’t hurt people or animals. It forms ____3____ (natural). It’s often just sand with a lot of water. This ___4___ (make) the sand soupy and runny. When the wet sand can no longer support weight, it is called “quick”.

In fact, ____5____ (find) quicksand is not very hard. A beach is a good place to see how water affects (影响) sand. In the area where sea water runs onto the land, the sand changes. Here, water sinks into (渗入) the sand, making the sand wet ____6__ soft. For a few seconds, the surface is like quicksand.

Sand is not ____7____ only thing that can become “quick”. Dirt, pebbles, and gravel (碎石) can also become quicksand under the right conditions. This means that quicksand forms when water mixes with one of ____8____ (this) materials in just the right way.

Quicksand is usually ____9____ (see) in wetlands, or watery places. It’s almost never seen in deserts though there is a lot of sand. Think about movie quicksand again. Though quicksand is not so scary as the movies show, you should still be ____10____ (care) when you meet it.

1.1.

A

B

C

D

解析：选films。类型：名词单复数 解析：those（那些）后面要接可数名词复数；film 复数直接加 s，填 films。

2.2.

A

B

C

D

解析：选as。类型：固定搭配 解析：固定短语 the same as，意为 “和…… 一样”。句意：真实流沙和电影里的流沙不一样。

3.3.

A

B

C

D

解析：选naturally。类型：副词 解析：修饰动词 forms（形成）要用副词；natural 形容词，副词形式 naturally（自然地）。

4.4.

A

B

C

D

解析：选makes。类型：一般现在时，主谓一致 解析：主语 This 是单数，全文为一般现在时，谓语动词用第三人称单数 makes。

5.5.

A

B

C

D

解析：选finding。类型：非谓语（动名词作主语） 解析：此处作句子主语，动词 find 要变为动名词 finding；动名词作主语，表示 “找到流沙” 这件事。

6.6.

A

B

C

D

解析：选and。类型：并列连词 解析：wet（湿润的）和 soft（松软的）是并列形容词，用 and 连接。

7.7.

A

B

C

D

解析：选the。类型：冠词 解析：固定搭配 the only，only 前面一般加定冠词 the，表示 “唯一的”。

8.8.

A

B

C

D

解析：选these。类型：代词变形 解析：materials 是复数，this（这个）改为复数 these（这些），one of these materials 这些物质中的一种。

9.9.

A

B

C

D

解析：选seen。类型：被动语态 解析：被动结构 be + 过去分词；see 的过去分词 seen。be seen 被看见、可见。句意：流沙通常在湿地被见到。

10.10.

A

B

C

D

解析：选careful。类型：形容词 解析：be 动词后面接形容词作表语；care 动词 / 名词，careful 形容词 “小心的”。be careful 小心。