By the time she (A10) school she (A11) a good command of three foreign languages.
A10:
а) had been left
б) has left
в) was leaving
г) left
A11:
а) has had
б) was had
в) had had
г) had been had

By the time she (A10) school she (A11) a good command of three foreign languages.

A10: г) left

A11: в) had had

A10- Г left

A11- В. Had had