Пожалуйста, помогите, нужно предложения ниже представить во времени Present Perfect. Мне нужны сразу переделанные предложения(правило я и сам знаю)
1.We heard about a 10-day expedition to the Ugra National Park.
2. The students participated in volunteer work such as cleaning the springs and paths in the forest.
3. We learned that most school students in Russia study Ecology and take part in conferences and even about modern ecological problems.
4. They learn how to put up tents, make a fare, cut wood and cook on an open fire.
5.They learn how to experience nature by using all their senses.