They shoulder the task of conducting research on the protection of rare plants or plants _____ extinction (灭绝).

The treatment was completely successful and the pain disappeared _______.

According to a report, Asian market ___________ 62 percent of the company’s revenue last year.

When he is in a difficult situation, his friends ____________, giving emotional and material support.

Any construction waste and household waste generated during construction must be _________ and taken away.