keep: keep, kept, kept, keeping
Keep to the schedule. (Present tense.)
It is kept in a box. (Past participle, present progressive.)
It is being kept in a safe place. (Past participle, present progressive.)
It was kept in good condition for a long time. (past participle, past perfect.)
He is keeping time to the music. (Present participle, present progressive.)
Don't keep doing that. (Present tense.)
Please keep this in a safe place. (Present tense.)
She is keeping it with her. (Present participle, present progressive.)