The plural form of "these" in the dative case is þessum. It is exactly the same for all three genders (masculine, feminine, and neuter).
As always with demonstrative pronouns, the noun that follows drops its definite article. Because indefinite nouns in the dative plural end in -um, this creates a predictable, rhyming pair, like þessum leikurum (these actors) or þessum hátíðum (these festivals).
Triggered by Prepositions
Many prepositions force the following words into the dative case. When discussing venues and performances, you will frequently use á (at/on) and í (in).
| It is always fun at these festivals. | Það er alltaf gaman á þessum hátíðum. |
| She is fantastic in these roles. | Hún er frábær í þessum hlutverkum. |
Certain expressions and phrasal verbs also require the dative, such as hrifinn af (impressed by / fond of) and klappa fyrir (to clap for).
| I am very impressed by these plays. | Ég er mjög hrifinn af þessum leikritum. |
| We clap for these actors. | Við klöppum fyrir þessum leikurum. |
Triggered by Verbs
Some verbs govern the dative case directly, without needing a preposition. When you believe (trúa), thank (þakka), or forget (gleyma) someone or something, those objects take the dative.
| We do not believe these actors. | Við trúum ekki þessum leikurum. |
| The kids thank these actors. | Krakkarnir þakka þessum leikurum. |
| I often forget these roles. | Ég gleymi oft þessum hlutverkum. |