 Hello. Hello. In the following, we will look at the morphological processes that define different types of words. In fact, there are two such processes, namely inflection and word formation. Other, more exceptional processes are not considered in this e-lecture. Let us look at the main formal differences between inflection and word formation first. Yes. Let's look at inflection. This process involves one base form, also referred to as free morph, and at least one morphological operation. Here are three examples. Walk, walked, that's concatenation. Mouth, mice, that's volcanic change. And go, went, that's apletion. Interestingly, sometimes several operations may occur simultaneously. In German Haushäuser or in present-day English, say, said, we find two operations, concatenation and volcanic change. And word formation processes? Well, word formation processes can be subdivided into two main types. Into derivation, where we have one base form to which one or several operations are applied. And compounding, where we combine several base forms. Thus, derivation is formally just like inflection. Compounding by contrast is different. In order to keep inflection and derivation apart, a set of criteria have been put forward. Let's look at them in detail. Okay. The first and maybe most important criterion is referred to as productivity. It defines the morphological process as fully productive if it applies to all members of a given class. Take the formation of the past tense, a typical inflectional process. All verbs have a past tense form, irrespective of the type of morphological operation involved. That is prefixing, suffixing, vowel change, and so on. So inflection is fully productive. Derivation, by contrast, is less productive. Take the formation of nouns from verbs, act, actor, swim, swimmer, but rain, rainer, or seam, seamer. So derivational processes do not apply to all members of a particular class. Well then, inflection does not change the word class of the stem, but derivation may do so. Take apply, applies, applying, and applied, they're all verbs. In derivational processes, by contrast, the word class may change as in act, actor, or able, enable. But it may also remain the same as in boy, boyhood, both are nouns, or happy, unhappy, where both are adjectives. To make it absolutely clear, inflection never changes the word class, but derivation may do so. But there are further criteria to keep inflection and derivation apart in present day English. Yes, for example, inflection doesn't involve a change of the stress pattern of the stem, and again, derivation may do so. Take the verb standardize. If we inflect it, it keeps its stress on the first syllable. In forms such as standardized, standardizing, whereas the addition of derivational suffix, asian, causes a stress shift to the third syllable, standardization. In some cases, stress shift is even accompanied by phonemic changes. For instance, if we add a ball as in move, moveable, to the verb apply, we get applicable. Yes, well, and furthermore, inflection is semantically transparent across the board. Derivation is not. If you add ed to a verb, the result is either past or past participle. Derivatives that are generated, for example, by the addition of ion, however, denote different things. In many cases, ion means the act of, but not in examples such as commission or television. But note, all these criteria are primarily based on present day English. In some languages, the criterion stability of stress pattern does not work. Here is an example from Welch, a Celtic language. Aval. Avalai. Or take Russian where the nominative and the genitive of a noun, that is, case inflection, may involve different stress patterns. Okay, let's summarize. Right. We said that morphological processes define different ways of building words. Formally, a distinction can only be drawn between compounding and the other processes. For this reason, we need additional criteria such as productivity, the stability of the word class, the stability of the stress pattern and semantic transparency to keep inflection and derivation and, more generally, inflection and word formation apart. Thanks for your attention.