Some verbs (for example, know and like) are nor normally used in this way.

They are "pucked," a new verb used by the American soldiers, taken from the military phrase "persons under control."

Intransitive verbs use either the agent series or the patient series.

Often a single verb will use more than one derivational suffix, resulting in very long words.

Some verbs from the seventh class can use both endings.

To create the perfective counterpart, verbs use various prefixes without any clear rules.

Either verb could optionally use the expression "used to" in English.

Many verbs simply have no past tense, and use the present form.

Some verbs of this type also use the frequentative or repetitive forms in the neutral voice and others do not.

A few verbs have special humble forms, used when the speaker is referring to him/herself in polite situations.