a year and half
a year and a half
a half and a year
half and a year
考查词组辨析。A. 表述不正确，应在half前加上a B. 一年半 C. 表述不正确，可以说one and half years，意思为一年半 D. 表述不正确。It was the first time that…后接过去完成时。
句意：那曾是一年半以来，我第一次直面夜空。故选B。
