New Words：

rare [rer] adj. 稀少的；稀罕的；珍贵的
rarer ['reərə] 形容词rare的比较级形式

Sample Sentences：

These rare tigers are protected by special laws.
The higher you climb up the mountain, the rarer the air is.
He's devoted his whole life to the protection of the rare animals.

New Words：

orchid ['ɔ:kid] n. 兰花
bulldozer ['bul.dəuzər] n. 推土机

Sample Sentences：

Can you operate a bulldozer?
Many kinds of wild orchid are becoming rare.
The wallpaper in our bedroom has a pattern of orchids.

rare[rer] adj. 稀少的；稀罕的；珍贵的

New Words：

some time 一些时间，一段时间
sometime 某个时候

some times 几次
sometimes 有时

Sample Sentences：

I need some time to relax.
I'll call you sometime tomorrow.
I have been to Japan some times.
We sometimes have dinner with our friends on the weekend.

New Words：

banner [ˈbænər] n. 横幅；大标题

Sample Sentences：

They were so excited that they kept waving banners.
The villagers carried a banner reading ‘ Save our Wildlife ’.
A banner ad at a site I sometimes visit reads "You are the 1, 000, 000th visitor! "

New Words：

spoil [spɔil] v. 破坏；搞坏；糟蹋；毁掉；溺爱；宠坏
过去式：spoiled
过去分词：spoilt

Sample Sentences：

The child was spoilt by his grandfather.
Our camping trip was spoilt by bad weather.
Your present behaviour would spoil your future.
The heavy rain has spoilt the flowers in the park.
He had spoiled the soup by putting in too much salt.