This class will deal with different kinds of null subjects from a cross-linguistic/language acquisition perspective. For instance, German sentences like "Regnet ja übelst", "Hat sich schon gemeldet" und "Nein, weil gegessen wurde" do not have a grammatical subject. We will compare such sentences with similar sentences from various typologically-different languages like English, Spanish, Italian, Bulgarian, Russian, Chinese etc. Alongside with pinpointing the differences between different types of null subjects and different classes of null subject languages we will also deal with the implications such cross-linguistic differences have in the domain of language acquisition, especially second language acquisition. In addition, we will look into the diachronic development of languages with respect to null subjects or in other words into how languages lose their null subjects.