Помогите выполнить задание

Question

Помогите выполнить задание

Валерий Ученик (4), на голосовании 2 дня назад

Используйте глаголы, заключенные в квадратные скобки, в соответствующем времени.

As fever (to persist) for about three weeks the patient's condition is very poor.
The researcher (to investigate) the origin of the inflammation for about a week before he drew a definite conclusion.
Some symptoms of the vascular impairment of the brain (to develop) gradually for some time before they became clearly marked.

Answer 1

As fever persisted for about three weeks, the patient's condition is very poor.

The researcher investigated the origin of the inflammation for about a week before he drew a definite conclusion.

Some symptoms of the vascular impairment of the brain developed gradually for some time before they became clearly marked.