根據(jù)句意和首字母填單詞：

There are four s　　　　 in a year.

單詞填空：根據(jù)所給括號(hào)中的詞填空。

Later, he became ________ in science very much. (interest)

單詞填空：根據(jù)所給括號(hào)中的詞填空。

What will be the population of the world by the end of the ________ century?(twenty-one)

單詞填空：根據(jù)所給括號(hào)中的詞填空。

I kept on ________ about the match. (think)

單詞填空：根據(jù)所給括號(hào)中的詞填空。

She didn't come to school yesterday because of ________. (ill)

單詞填空：根據(jù)所給括號(hào)中的詞填空。

Look! How ________ Jim is laughing. (happy)

單詞填空：根據(jù)所給首字母填空。

We can't leave the students by t　　　　.

單詞填空：根據(jù)所給首字母填空。

Edison was a great American i　　　　.

單詞填空：根據(jù)所給首字母填空。

Satellites are used by people for studying the u　　　　.

單詞填空：根據(jù)所給首字母填空。

Beijing is the c　　　　of China.