New Words：
plain [plein]
n.平原
adj.清楚的；简单的；坦白的；平常的；朴素的；纯的
Sample Sentences：
She always wears plain clothes to work.
The meaning of the sentence is very plain.
To be plain with you, I know nothing about it.
When we reached the top of the mountain, a wide plain came into view.
New Words：
monk [mʌŋk] n. 和尚；僧侣；修道士
frock [frɔk] n. 连衣裙；女上装；罩袍；僧衣
Sample Sentences：
This monk wears a gray frock.
I was wondering if you might have a spare frock for me.
The monk and the monkey continued their journey over hills and across plains.
plain [plein] n. 平原
New Words：
bell [bel] n. 铃（声）；钟（声）；钟状物；电铃（声）
Sample Sentences：
Ring the bell to see if they're in.
Hearing the bell, we raced to the class.
A loud bell waked me from a deep sleep.
The young monk clangs the bell every morning.
monk [mʌŋk] n. 和尚；僧侣；修道士
clang [klæŋ] v.（使）发出铿锵声；（使）叮当作响
New Words：
jellyfish ['dʒelifiʃ] n.水母；海蜇
thumbnail ['θʌmneil] n. 拇指甲
Sample Sentences：
You can get a nasty sting from a jellyfish.
The smallest jellyfish may only reach about the size of your thumbnail.
New Words：
submarine ['sʌbməri:n]
n.潜水艇
adj.水下的；海底的
Sample Sentences：
The submarines surfaced.
The submarine rose to the surface.
Why can a submarine float and sink?Submarine earthquakes often happen in ocean.