They serve an eighteen-month probationary period that starts at the time they enter the academy.

She then described in detail her very personal involvement with him over an eighteen-month period.

Instead of the designated eighteen-month period of time, Rodin employed a lengthy seven years to finish the work.

For a special effects company that had been in existence less than three years, the eighteen-month period for completing The Frighteners was largely stressful.

Over an eighteen-month period, the duo's manager Simon Napier-Bell took regular trips to Beijing.

The 92 person study was conducted over an eighteen-month period.

This, coupled with high maintenance costs, built up debts of over £6 million in an eighteen-month period.

Recorded over an eighteen-month period in the band's own studio, this album showcases a greater depth in songwriting and instrumentation than previous releases.

In an eighteen-month period in 1913-1914, Harris baptized over 100,000 new converts.

There will be an eighteen-month period of peace, but in the three months following that, the rest of the Seal judgments will fall on the earth.