passive voice (present perfect)

herbal plants ______ for years to help solve medical problems.

• has been used

• have been used

Aloe vera ______ to help skin allergies

• has been found

• have found

several hospitals _____ for the citizens of this city.

• have been build

• have been built

ginger _______ to help curing bloated stomach

• has been used

• have been used

The Lab _______ for specific purposes

• has been sterilized

• have been sterilized

Nina ______ by her mom to find betel leaves.

• have been told

• has been told

Her medical concotion _______ by others.

• has been used

• have been used

Temulawak ______ to relieve constipation.

• has been using

• has been used

several herbal plants _____ to exchange chemical medicines.

• has been used

• have been used

aloe vera _______ to cure skin allergies.

• has been proven

• has been proved