Open the brackets and use the correct tense from. 1.jane(to learn) a lot of things about animals by friday. 2.the students (to prepare) for the trip by that time yesterday. 3.i was surprised,because i never (to see) a grizzly bear. 4.the forest was full of rubbish.somebody (to throw) it. 5.when the students (to return) their friends ( to go) away. 6.when we ( to reach) the forest the travellers already ( to camp) 7.the students ( to solve) some ecological problems in the camp by sunday.