We were afraid _____(be)very late for the concert.

We were afraid _____(be)very late for the concert.
We were afraid _____(be)very late for the concert.

We were afraid _____(be)very late for the concert.
We were afraid to be (be)very late for the concert.
afraid的用法:
be afraid + of + 名词/动名词
be afraid + to + 动词原形
be afraid + (that) + 从句

to be
be afraid to do 害怕做…… 是固定搭配

to be吧！

We were afraid __of being___(be)very late for the concert.
be afraid of sth/doing sth, 是固定搭配。表示，担心，恐怕等，属于程度较轻的一类。