How long__we take part in the college entrance examination?

问题描述:

How long__we take part in the college entrance examination?
only less than 1 year
A is it since B will it be before C is it when D will it be since

这道题应该选BIt +is/has been +时间段+since +从句(一般过去时)It+was +时间段+since +从句(过去完成时) 这两个句型的中文意思都是自从...以来有多久了It +will +be +时间段+before从句.意思是要过多久.才.It +b...