since 时间的时态,什么时候用现在完成时,什么时候用现在完成进行时she_______in the elementary sc_英语解答

since 时间的时态,什么时候用现在完成时,什么时候用现在完成进行时
she_______in the elementary school since she graduated from college in 1990.
a/ taught b/ has been teaching c/ was teaching d/ has taught

人气：120 ℃　时间：2019-08-18 01:23:14

解答

选择B吧.现在完成时和现在完成进行时的区别：前者强调动作从过去持续到现在,而后者则不仅强调动作从过去不间断持续到现在,还包含将要继续持续下去的意思.如：It has rained for three days.（雨已经下了3天了）； It...