Toefl 3.kmf ((free))

The solvent, which she had been testing for heat resistance, unexpectedly reacted with naturally occurring minerals in the soil. Within weeks, a patch of barren land near the lab began to show unusual plant growth. Periwinkle and clover, species not seen in that area for decades, sprouted denser and greener than in surrounding fields. Intrigued, Elena put her engineering project on hold.