Grammatik1

Swedish verbs use the same form for all persons in the singular and in the plural.
The tennses in Swedish form two time levels.the'now-level' and the' then-level'
The now-level
Present(stem+-r)
Han pratar med henne nu.(nu) He's talking with her now.(now)
Han pratar mycket.(ingen speciell tid) He talks a lot.(no special time)
Han pratar med henne i morgon.(framtid) He will talk to her tomorrow.(future)

Perfect(har+supine)
The perfect is used
a.when something has happended before now,but without any specified time.
Han har bott i Indien. He has lived in India.
De har redan pratat med henne. They have already spoken to her.
b.together with a time marker belonging to the now-level.
Han har skrivit brev idag. He has written letters today.
Jag har varit sjuk hela/den här veckan. I've been ill the whole week/this week.
Hon har inte haft semester i år. She hasn't had any vacation this year.
c.about the future in a situation when you speak about two or more things you plan to do.
När jag har ätit ska jag ringa till henne och be om ursäkt.
After I have eaten,I will call her and apologize.
Han tänker studera på universitetet när han har slutat gymnasieskolan.
He's going to study at the university,after he has finished secondary school.

Future
The future can be expressed in several ways.There is no special verb form express it(like will)
Han talar med henne i morgon. (present tensen+time maker)
He will speak to her tomorrow.
Han ska tala med henne(i morgon). (ska+infinitive=plans to)
He will speak to her(tomorrow).
Han tänker tala med henne(i morgon). (tänker+infinitive=plans to)
He is going to/intends to speak to her(tomorrow).
Han kommer att vara trött(i morgon). (kommer att+infinitive=a prediction)
He will be tired(tomorrow).
Det kommer säkert att regna hela dagen.
It's certainly going to rain the whole day.

The present tense,tänker and ska+the infinitive often express that something has decided or planned to do something,that he/she is able to control or influence.
Kommer att+the infinitive expresses a prognosis or a prediction,i.e. something you normally cannot control or influence.