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study studied have studied had studied
not to study not studying have not studied did not study
the all day the whole day whole the day whole day
Have I I have Had I I had
must;must had to;have to had to; must have to;must
have been working was working have worked worked
should study may have studied should have studied must have studied
I'm going to see my grandma this Sunday I'm going there with Tom I have to study for a test I have no time this Sunday
used to learn was used to studying have studied didn’t use to study
study studying learning studied
am studying was studying will study would study
to have studied to study to be study to have been studying
studying having studied to study to have studied
to have studied to study to be study to have been studying
to have studied to study to be study to have been studying