Pupils是可數名詞嗎

例句：

The school began in 1920, with only ten pupils.

這所學校創建於1920年，當時只有十名學生。

Several pupils were designated as having moderate or severe learning difficulties.

幾名學生被認定有一定或嚴重學習困難。

The school has come under attack for failing to encourage bright pupils.

這所學校因未能鼓勵聰明學生而受到非難。

The school has over 850 pupils.

這所小學有850多名學生。