One of the most common mistakes among German learners who just started off is overuse of the German ending -ung, which looks like the English ending -ing but has very little in common with it.
First of all, you should remember there are no progressive (continuous) tenses in German. The form “verb+ung sein” (seemingly the equivalent of “be verb+ing” in English) doesn’t make any sense at all, to such a degree you probably wouldn’t even be understood if you used it. For example, both “I am practising” and “I practise” should be translated as:
The latter sentence literally means “I am exercise” and would raise a few eyebrows. Similarly, we cannot use -ung to create adjectives from verbs. The usual way to translate “verb-ing noun” into German is through compound words. For example, “It is drinking water” would be:
Finally, -ing is used to express the activity itself in English, but not in German. To express the activity a verb represents, we use the capitalized infinitive, often preceded by “das”. For example, “He loves swimming” would be:
At this point, you are probably asking whether the ending “-ung” in German has any function at all. It has, but an unexpected one. It usually has the same function as -ment, -tion, -ance, and similar in English, e.g.
bewegen (to move) – Bewegung (movement)
erklären (to explain) – Erklärung (explanation)
erinnern (remember) – Erinnerung (remembrance)
It is customary to use it only with certain verbs. Just like we wouldn’t say “do-ment” or “do-tion” in English, we cannot say “Tunung” (from tun, to do) in German; however, you will have to memorize when Verb+ung makes sense and when it doesn’t—there is no general rule. Also, the meaning of the -ung noun is sometimes only inspired by the original verb and is not directly derivable from it, e.g.
ordnen (to order) – Ordnung (arrangement, regulation)