Polite Progressive Form
Polite Progressive Form is used in a formal situation. You should use it to talk to teachers and elderly people.
Polite Present Positive Progressive Form
てForm + います
Polite Present Negative Progressive Form
てForm + いません
Polite Past Positive Progressive Form
てForm + いました
Polite Past Negative Progressive Form
てForm + いませんでした
Plain Progressive Form
Plain Progressive Form should be used among friends or people you feel close to.
Plain Present Positive Progressive Form
てForm + いる
Plain Present Negative Progressive Form
てForm + いない
Plain Past Positive Progressive Form
てForm + いた
Plain Past Negative Progressive Form
てForm + いなかった