Learn Dutch: Gisteren kletsten we in de kantine. - Yesterday we chatted in the canteen.

The infinitive is kletsen (to chat). Remove the -en to find the stem: klets. The last letter is s, which is one of the voiceless consonants in 't kofschip. This means it gets the voiceless past tense ending. Because the subject we is plural, we add -ten to make kletsten.

Why does kletsten have two 't's right next to each other?

The first t is part of the verb's stem (klets). The second t comes from the past tense plural ending (-ten). When you put them together (klets + ten), you get kletsten.

Why is the word order kletsten we instead of we kletsten?

Because the sentence starts with the time word Gisteren (yesterday). In Dutch, if you start a sentence with anything other than the subject, the verb comes first and the subject immediately follows it. This rule is called inversion.

Could I use wij instead of we in this sentence?

Yes, you can use wij, but we is much more common for everyday actions. You only use wij if you want to put special emphasis on it, like pointing out that WE chatted while someone else was working. Since there is no special emphasis here, the unstressed we is the best choice.