1. melt [melt] vt./vi. (使)熔化，融化；使融合；使心软化；逐渐消失

The hot sun melted the snow.

灼热的太阳使雪融化了。

The sea melted into sky on the horizon.

在地平线上，海和天融为一色。

My heart just melted when I saw her crying.

我看到她哭就心软了。

His savings have melted away.

他的积蓄已经花光了。

The demonstrators melted away when the police arrived.

当警察赶到时，示威的人群逐渐散开。

2. necessity [nɪ'sesɪtɪ] n. 必需品；必要，需要；必然的事物

Food and clothing are the basic necessities of life.

食物和衣服都是基本的生活必需品。

Out of necessity or out of interest, people go back to school for the common goal to improve themselves.

不管是出于需要，还是出于兴趣爱好，人们重返学校是为了一个共同的目标----提高自己。

the necessity of (doing) sth 某事的必要性

We were discussing the necessity of employing more staff.

我们在讨论是否需要雇用更多员工。

Living in Tokyo is an unfortunate necessity for him.

生活在东京对他来说既不幸又无奈。

of necessity 势必，必定

Many of the jobs are, of necessity, temporary.

有许多工作岗位势必是临时性的。

3. necessitate [nɪ'sesɪteɪt] vt. 使成为必需，需要

necessitate sth

The increase in population necessitates a greater food supply.

人口的增加需要更多的食物供应。

necessitate doing sth

Increased traffic necessitated widening the road.

交通量增大，这就需要拓宽道路。

4. capable ['keɪpəb(ə)l] adj. 有能力的，能干的，有才能的

She's a very capable speaker.

她是一个非常有能力的演说者。

capable hands 能手，高手

I'll leave the organization in your capable hands.

我要把组织工作交给你这位能手。

be capable of 有能力做某事

The kitchen is capable of catering for several hundred people.

这间厨房可为数百人提供饮食。

He doesn't seem to be capable of doing this job by himself.

他似乎没有能力独自做这项工作。

capability [‚keɪpə'bɪləti] n. 才能，能力

Animals in the zoo have lost the capablity to catch food for themselves.

动物园的动物已经丧失自己捕食的能力。

5. capacity [kə'pæsɪtɪ] n. 容量，容纳力；生产力；能力，才能；职位，身份

The room had seating capacity for about 80.

这房间能坐80个人左右。

be filled to capacity

All the hotels were filled to capacity.

所有的宾馆都住满了。

The factory has been working at full capacity.

这家工厂已经在全力生产了。

He has a great capacity for hard work.

他很能吃苦。

in one’s capacity as… 以…的身份

I attended the meeting in my capacity as chairman of the safety committee.

我是以安全委员会主席的身份参加这次会议的。