ay’s fiercely competitive society,； people only care about what achievements you _______, not your efforts.

加横线的词中与其他三项的用法不同的一项是（ ）

She is ______years old. This is her _______birthday.

Life ____ be much happier if we ____ only be born at the age of 80 and gradually approach 18.

It is dark outside, so please____ your step while going down the stairs.