New words：

thunder [ˈθʌndər] n. 雷；雷声
thunderstorm [ˈθʌndərˌstɔrm] n. 雷暴；雷雨；雷雨交加

Sample Sentences：

Outside, thunder boomed and crashed.
Turn off the TV set in case of thunderstorm.
The day was heavy and still. It would probably thunder later.

New words：

clap [klæp]
v.拍手；鼓掌
n.鼓掌；拍手；掌声；拍手声；霹雳声；砰然巨响

Sample Sentences：

We clapped when the singer finished.
He clapped me on the back and laughed.
The teacher clapped the ruler on the desk to quiet us.

A loud clap of thunder woke me up.
A single clap started, then everyone joined in.

thunder [ˈθʌndər] n. 雷；雷声

New words：

crow [krəʊ]
n.乌鸦；(像雄鸡的)啼叫声，喔喔叫声
v.（尤指在清晨）啼叫，打鸣；自鸣得意；欢叫

Sample Sentences：

The crows crowed at dawn.
He crowed about winning the game.
Crows are known for their intelligence.
The cock clapped his wings and crowed.
Don’t crow so loud—you might not win next time.

clap [klæp] v.拍手；鼓掌

New words：

forecast [ˈfɔrˌkæst]
n.预测；预报
v.预测；预报

Sample Sentences：

Scientists forecast more storms this season.
They forecast that the team will win the game.

The weather forecast says it will be sunny.
The forecast of a storm made us cancel the picnic.

New words：

symbolize [ˈsɪmbəˌlaɪz] v. 象征；是…的象征；代表

Sample Sentences：

A white dove symbolizes peace.
The festival symbolizes the start of spring.
The use of light and dark symbolizes good and evil.