1. Sea horses are harvested.
Sea horses are used in traditional Chinese medicine. (Use prep. phrase telling reason).

Sea horses are harvested for use in traditional Chinese medicine.

2. Men are motivated and empowered.
Men feel needed. (Use clause telling time).

Men are motived and empowered when they feel needed.

3. Thai writing was dominated by “literature for life,” a movement that called for social justice.
This happened during the 1970s and 1980s. (Use prep. phrase telling time)

Thai writing was dominated by "literature for life," a movement that called for social justice during the 1970s and 1980s.

4. The Martians and Venusians had been quite happy.
They lived in their separate worlds. (Use verbal phrase telling how).

The Martians and Venusians had been quite happy, living in their separate worlds. or

Living in their separate worlds, the Martians and Venusians had been quite happy.

5. The two major English-language dailies have proven to be remarkable success stories.
The dailies meet the high standards of journalism. (Use while and verbal phrase).

The two major English-language dailies have proven to be remarkable success stories while meeing the high standards of journalism.

6. You will find that it isn’t half as scary as you thought.
You can find the courage to tackle your phobia. (Use clause telling a condition).

You will find that it isn't half scary as you thought if you can find the courage to tackle you phobia.

7. A victim of gang rape recalled the traumatic night.
Her voice was cracked with emotion. (Use an absolute)

Her voice cracked with emotion, a victim of gang rape recalled the traumatic night.

8. The Thai government bought shares of two of the three major Thai airlines of the time.
The government wanted to stimulate the growth of a truly national airline of its own. (Use a verbal phrase telling a reason or purpose).

The Thai government bought shares of two of the three major Thai airlines of the time to stimulate the growth of a truly national airline of its own.

Source: Vessakosol, Pimpan. 2000. Sentence Composition. Thammasat University Press.