"We have plates."
Translation:We hebben borden.
It's explained in one of the Basic lessons. In general the verb's infinitive form always ends with the -en ending. If you remove that suffix you get a stem. You use a stem of verb for 1-st person singular, stem with added -t for other singulars and the full infinitive (so with -en) for all plurals. There are some extra rules about vowel length and consonants doubling (or un-doubling to be more precise). So if you take the verb drinken your stem is drink. Thus you have ik drink (1-st person singular), je drinkt, hij drinkt (both singular and not 1-st person), we drinken, jullie drinken, zij drinken (all plurals). Yet the verb hebben is an irregular verb (one of just 6) so in 3-rd singular you get the irregular form heeft (other forms follow the regular rule except for u, but that one want covered yet)