帮我解决下初二英语题 求大神围观

问题描述:

帮我解决下初二英语题 求大神围观
They didn't understand ____ they didn't know ____ ____ ____.
他们不懂因为他们不知道整个经过.

Mary c____ come here today because she is sick.根据首字母填空.

1 because what has happened
2 can't或couldn't