Future Tense

The Czech language has two ways how to express the future.

1) Imperfective verbs: BÝT, to be (in future tense) + imperfective infinitive of the main verb

Imperfective verbs are used to express an uncompleted activity and repeated activity.
Sedět - to sit, to be sitting
Zpívat - to sing, to be singing

BÝT, future tense (singular - plural)
1. person: budu - budeme
2. person: budeš - budete
3. person: bude - budou

já budu - I will be
ty budeš - you will be
on, ona, ono bude - he, she, it will be
my budeme - we will be
vy budete - you will be
oni, ony, ona budou - they will be

"Budu, budeš,..." with infinitives have the same meaning as (I, you, she,....) will be doing the verb in English.
Já budu dělat. - I will be doing. (dělat, to do)
Ty budeš zpívat. You will be singing. (zpívat, to sing)

The imperfective future is used for:

• fugure unfinished activities in progress
• activities which will repeatedly happen in the future

Zítra budeme péct dort. (We will be baking a cake tomorrow - it will take some time before we wil finish it.)
Budeš se učit česky každý den. (You will learn Czech every day - i will take place regularly)

2) Perfective verbs: Changing the verb
The perfective verb is usually changed by adding prefixes. The choice often depends on the particular verb, and we must memorize each verb.
The conjugation of the future perfective verb is then done for the present tense.

Perfective verbs describe a one-time, finished action within a certain time frame.
vypít - to drink up, finish drinking
posadit - to sit down, finish sitting down

The imperfective future is used for:

• completed activities and actions
• providing plain information and facts, the progress is not important
• one-off, not repeated action

Zítra si přečteme tu knihu. (Tomorrow we will read the the book - we will finish it)
Napíšu ten úkol zítra. (I will write that homework tomorrow - I will write it tomorrow, and I will finish it.)

Imperfective - Perfective future:
zpívat (to sing, to be singing, imperfective)
zazpívat (to sing, to have a sing, perfective)
Já budu zpívat písničku. - I will be singing a song. (imperfective, continuous event, the act of singing is important)
Já zazpívám písničku - I will sing a song. (perfective, one-time event, the action is not important - the important fact is that I will sing a song.)

Negative Future Tense
Imperfective verbs: adding prefix ne- to the future form of být
Já budu zpívat písničku. - Já nebudu zpívat písničku.
Já budu tancovat. - Já nebudu tancovat.

Perfective verbs: adding prefix ne- to the main verb
Já zazpívám písničku. - Já nezazpívám písničku.
Já zatancuju. - Já nezatancuju.

Reflexive verbs
Reflexive verbs have "se" or "si" added to the main verb.

povídat si - to talk, to have a talk
mýt se - to wash oneself

The reflexive verbs' future tense is formed for the non-reflexive verbs. "Se" and "Se" do not change. They usually stand after the main verb. However, they can often stand before the main verb.
There is no general rule for that, but when the subject is expressed, "se" or "si" moves before the main verb.
If the subject is not expressed, "se" or "si" moves before the infinitive of the main verb.

On se bude mýt. (He will be washing himself.)
Bude se mýt.(He will be washing himself.)
Budou si povídat. (They will be talking.)
Oni si budou povídat. (They will be talking.)

Reflexive perfective verbs:
Usually, when the subject is expressed, "se" or "si" moves before the main verb. Otherwise, it remains behind the verb.
Zazpíváme si. (We will sing.)
Oni si zazpívají. (They will sing.)