Sweep is present tense, swept is both the past tense and past participle form of the verb sweep.
Use wasn’t for singular subject and weren’t when the subject is plural, except when communicating in the subjunctive mood.
‘Was’ is for first-person and third-person singular subjects past tense, and ‘were’ for second-person and third-person plural subjects. With the subjunctive mood, use ‘were’ in all cases.
Both mistook and mistaken are past forms of the present tense verb, mistake. Mistook is the simple past tense, whereas mistaken is the past participle form.
The irregular verb mean only has one past verb form: meant. Meant is both the simple past tense and past participle form of the verb ‘mean’.
The past tense of lie down is lay down, and the past participle is lain. The past tense of lay (something) down on (something) is laid.
Hopefully you haven’t wept over not knowing the past tense of weep. Here’s a hint, it’s in the previous sentence: wept and had wept are the past tense and past participle of weep.
Forbid has three verb forms: forbid, forbade, and forbidden. Forbade is the simple past tense, and forbidden is the past participle form of the verb.
The verb forget has three main forms: forget (present), forgot (past) and forgotten (past participle). Read this post to refresh your memory on the verb, to forget.