Open the brackets and use the correct tense from.1.Jane(to learn) a

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.
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