my older sister has studied Physics since eight months.这句话错在哪里?
问题描述：
my older sister has studied Physics since eight months.这句话错在哪里?
答
since后的时间状语时点时间所以在与完成时态连用时我们用since+短时间+ago. 本句改为my older sister has studied Physics sice eight months ago
答
since eight months ago
或
for eight months
答
since应该改成for
意思是我姐姐学习物理八个月了.