When to use “ist es” and when “es ist”?

Question

I am currently learning German and I am having a bit of trouble with word order, especially with the two words *es* and *ist.* For example, contrast the following sentences: > Es ist eine Katze. > Manchmal ist es kalt. I really don’t know what rules there are especially for these cases. A quick search on Google didn’t yield any rules and I’m having a hard time figuring out which to use when. So the question is: When do you have to use *es ist,* when do you have to use *ist es?*

Answer 1

The default sentence structure is Subject-Verb-Object, e.g. "Es ist kalt." ("Es" = subject, "ist" = verb, "kalt" = object). However, the subject and the verb are inverted in questions and when the sentence starts with a transition, e.g. "Ist es kalt?" (question) or "Manchmal ist es kalt." (the sentence starts with the transition "Manchmal"). This also happens in sub-clauses using a subordinating conjunction, such as "weil", e.g. "Ich trage einen Mantel, weil es kalt ist."