Short object pronoun clitics

Czech has two sets of object pronouns: short and long. The strictly short dative forms (mi, ti, mu) and accusative/genitive forms (tě, ho) are always unstressed. Other forms like jí, nám, vám, jim (dative), mě, nás, vás (accusative/genitive), and ji, je (accusative) act as unstressed clitics in neutral sentences, but they can also bear stress and stand in the first position when emphasized. (Note: The genitive counterparts of ji and je are jí and jich. In formal Standard Czech, the official long/stressed accusative and genitive form of já is mne, though mě is widely used in practice.) The demonstrative to often occupies the accusative slot at the end of a clitic cluster, but it can also stand in the first position and bear stress (e.g., To mu nedám.). When acting as clitics, these pronouns are the absolute default in everyday speech and writing and must follow strict placement rules.

1. The Second Position Rule
Short pronouns must sit in the second structural position of their clause (second-position clitics). This means they attach to the first stressed constituent. Note that a "constituent" can be a single word or a whole phrase:

• Zítra ti zavolám. (I will call you tomorrow. – After a single adverb)
• Můj nový kolega ho viděl. (My new colleague saw him. – After a multi-word subject phrase)

Crucially, the coordinating conjunctions a (and), i (and/even), ale (but), and nebo (or) do NOT count as the first position. Clitics skip over them and attach to the next stressed word. However, conjunctions like ani (nor/not even), as well as subordinating conjunctions (like že), DO count as the first position.

2. The Clitic Cluster Order
When a sentence has multiple clitics, they must follow a strict internal order. The sequence is: Auxiliary/Conditional verbs (past tense: jsem, jsi, jsme, jste – note that in the 3rd person, the auxiliary is dropped entirely, e.g., On se smál, not *On je se smál; conditional: bych, bys, by, bychom, byste) → Reflexive pronouns (se/si) → Dative pronoun → Accusative or Genitive pronoun. Note that positive present tense forms of the verb být (jsem, jsi, jsme, jste) are only strict second-position clitics when functioning as past-tense auxiliaries. When used as a copula or existential verb, they can bear stress and stand in the first position (e.g., Jsem student.). Negative present tense forms (nejsem, nejsi, nejsme, nejste) are also NOT clitics; they carry stress and can stand in the first position. Past tense negation is formed by attaching ne- to the main verb (the l-participle), while the auxiliary remains positive and stays in the clitic cluster (e.g., Neviděl jsem ho.). It is especially important to remember that the dative clitic comes before the accusative clitic (or genitive clitic):

• Dám mu to. (I will give it to him. – mu is dative, to is accusative)
• Bojím se ho. (I am afraid of him. – ho is genitive)

Important Note: When the second-person singular past auxiliary jsi meets the reflexives se or si, they obligatorily fuse into ses and sis (e.g., Koupil sis to? – Did you buy it for yourself?). The auxiliary jsi also obligatorily fuses with subordinating conjunctions ending in vowels, such as že + jsi = žes, aby + jsi = abys, and kdyby + jsi = kdybys. Additionally, in casual spoken Czech, this jsi often shrinks and attaches to other preceding words as -s (e.g., Kde jsi byl? → Kdes byl?).

3. When NOT to use short forms
Because strictly short forms carry zero emphasis and cannot bear stress, you must switch to short clitics versus long pronouns (like mně, tobě, jemu) in specific situations. Unlike clitics, long forms escape the second-position rule and can be placed anywhere in the sentence, including the first position:

• After prepositions: Do not use strictly short forms after prepositions (e.g., use pro tebe, not *pro tě). Note that 3rd-person pronouns take an n- prefix after prepositions (e.g., pro něho/něj).
• For emphasis or contrast: If you want to say "Give it to ME (not him)", you must use the long form (or an inconstant clitic that can bear stress).
• At the start of a sentence: Strictly short forms cannot be the first word.