Ukrainian verbs have several forms. These forms show whether the person doing the action is participating in the dialogue, and whether there is one person or several people doing the action.
All the forms are:
- 1st person singular: люблю́ ‘like’ (it’s used when the speaker is the only person doing the action; it can only be used with the pronoun «я» ‘I’);
- 2st person singular: лю́биш ‘liketh / like’ (it’s the original form used when the listener is the only person doing the action; it can only be used with the pronoun «ти» ‘thou/you’);
- 3st person singular: лю́бить ‘likes’ (it’s used when the person doing the action doesn’t participate in the dialogue; it can be used with pronouns like «він» ‘he’, «вона» ‘she’, «воно» ‘it’ and with a lot of different nouns like «кіт» ‘a cat’);
- 1st person plural: лю́бимо ‘like’ (it’s used when the speaker belongs to the group doing the action; it can only be used with the pronoun «ми» ‘we’);
- 2nd person plural: лю́бите ‘like’ (it’s used when the listener belongs to the group doing the action [and the speaker doesn’t belong to it]; it can only be used with the pronoun «ви» ‘you’);
- 3st person plural: лю́блять ‘like’ (it’s used when the action is done by a group of people/things that includes neither the speaker not the listener; it can be used with the pronoun «вони» ‘they’ and with a lot of different nouns like «коти́» ‘cats’).
However, the system is not very logical because of politeness. When Ukrainians are polite, they refer to a listener as if there are several of listener. So, you use plural forms (Ви лю́бите ‘you like’) instead of singular forms (ти лю́биш ‘thou liketh / you like’).
In English, a similar process is complete: the people were so polite that the old 2nd-person singular form (thou liketh) became completely unused, replaced with plural form (you like), which is used both for plural and singular.
In Ukrainian, the process is not complete, and ти лю́биш is still used a lot. But you use it in situations which don’t require extra politeness: when speaking to friends, or people you perceive as peers. Also, it’s used when speaking to children.