To say for example what happened in the past you would use the suffix ´di´ (the past tense suffix)

di/dı/du/dü

(depending on vowel harmony)

Let´s do an example

Let´s take the verb ´kalmak´ - to stay

first take the ´mak´ away leaving you with just the verb base ´kal´

then can you see that the last vowel in the verb is ´a´

so we use ´dı´

kal-dı

kaldı

Now let´s take the verb ´gelmek´ - to come

First take the ´mek´ away leaving you with just the verb base ´gel´

then you can see that the last vowel in the verb is ´e´

so we use ´di´

gel-di

geldi

If the last letter in the verb is either

k p ç t

then the ´d´ will change to ´t´

ti/tı/tu/tü

example:

gitmek - to go

take the ´mek´ away and you are left with the verb stem ´git´

the ´i´ is the last vowel in the verb 

so we use ´ti´

git ti

gitti

I came - gel di m

You saw - gör dü n

He stayed - kal dı

We went - git ti k

You put - koy tu nuz

They did - yap tı lar 

To turn past tense sentences negative simply include ´me/ma´

example:

gel me di m 

gelmedim (I did not come)

al ma dı n

almadın (you did not take)

koy ma dı

koymadı (she did not put)

gör me di k

görmedik (we did not see)

ye me di niz

yemediniz (you did not eat)

Ziyaret et me di ler

Ziyaret etmediler (they did not visit)

Asking question in past tense

to ask a question simply add ´mi?´ (mı/mu/mü) to the end of the sentences

example:

geldim mi? - did I come?

gördün mü? - did you see?

kaldı mı? - did he stay?

ziyaret ettik mi? - did we visit?

unuttunuz mu? - did you forget?

yapdılar mı? - did they do?

Try to do your own sentences until you can be sure that you have learnt this suffix :)