Fresh water is very important to life because no one can live without it. Yet it is one of the limited and most endangered natural resources on our planet.

It was Tom _______ to help us.

It's my ____ ceremony next week; I think my parents are looking forward to it more than I am.

Điền mạo từ: a/an/the/x

There was (1) ________knock on (2) ________door. I opened it and found (3) ________small dark man in (4) ________blue overcoat and (5) _______woolen cap.

The society was set up to _________ endangered species from extinction.

Tìm từ đồng nghĩa với từ gạch chân:

Our country's natural and cultural potential for ecotourism is well known.

Tìm từ đồng nghĩa với từ gạch chân:

Their activities are not based on the ecotourism principles.