Learn Dutch: Ondanks het slechte weer bezoeken veel onderzoekers de symposia in de musea. - Despite the bad weather, many researchers visit the symposia in the museums.

Words of Latin or Greek origin ending in -um, like symposium and museum, traditionally form their plural by changing the -um to -a. In modern Dutch, the regular plurals symposiums and museums are also correct and very common, but you will often see the classical -a endings in formal writing or academic contexts.

Why is the verb bezoeken placed before the subject veel onderzoekers?

This is because of inversion. In Dutch, the conjugated verb is almost always the second element in the sentence. Since this sentence starts with the descriptive phrase Ondanks het slechte weer (element 1), the verb bezoeken takes the second spot. The subject veel onderzoekers is then pushed immediately after the verb.

Why does slecht have an -e at the end in het slechte weer?

Weer is a het-word (a neuter noun). When a het-word is used with the specific article het, the adjective before it gets an -e ending. If you used the unspecific article een, it would just be een slecht weer, but with het, the extra -e is required.