You may have occasionally seen sentences like the following: Sie sagte, er spreche sehr gut Deutsch. 

You may think, er spreche? What is going on here?

This structure is an example of what is known as the indirekte Rede (in English "reported speech"), which is used more often but not exclusively in written German and formal reporting or storytelling. Sentences like this will involve the verb sagen or other verbs used to talk about what people think and say, such as antworten, äußern, behaupten, berichten, denken, erklären, fragen, glauben, or meinen.

In instances where someone's speech or thoughts are reported, you may see the subjunctive (Konjunktiv I) employed, like in the sentence above. For regular verbs, some of the endings are indistinguishable from other tenses, but some are very different. Here is the complete Konjunktiv I conjugation of the verb sprechen, and here are examples of how it would be used with reported speech:

Er sagte, ich spreche sehr gut Deutsch. ("He said I speak very good German.")
Er sagte, du sprechest sehr gut Deutsch. ("He said you speak very good German.")
Er sagte, er/sie spreche sehr gut Deutsch. ("He said she/he speaks very good German.")
Er sagte, wir sprechen sehr gut Deutsch. ("He said we speak very good German.")
Er sagte, ihr sprechet sehr gut Deutsch. ("He said you speak very good German.")
Er sagte, Sie/sie sprechen sehr gut Deutsch. ("He said they speak very good German.")

In the following examples, you can see the same conjugation pattern with a few other verbs: 

Der König hatte sie nicht eingeladen,

The King hadn't invited her,

weil es hieß, sie habe ein böses Herz.

because it was said she had an evil heart.

Caption 19, Märchen - Sagenhaft - Dornröschen

 Play Caption

Er verband ihm das Bein,

He bandaged his leg,

fragte ihn nicht, wohin er wolle, woher er käme.

did not ask him where he was going, where he had come from.

Captions 7-8, Janoschs Traumstunde - Der Wettlauf zwischen Hase und Igel

 Play Caption

Der hat mir erzählt, er sei echt nur...

he told me that he really just is...

Er fahre eigentlich Mercedes

He actually drives a Mercedes

und kleide sich deshalb so schräg ...

and the reason he dresses so weirdly...

Captions 30-31, Yello-Biographie - Ein Leben für die Avantgarde

 Play Caption

You may have noticed that kommen is irregular. One other irregular verb that you have likely seen conjugated like this is sein:

Von daher werde ich nicht tanzen,

Therefore I won't be dancing,

so dass ich behaupten kann, ich sei ein brillianter Tänzer,

so I can claim that I'm a brilliant dancer

und niemand kann es konterkarieren.

and nobody can disprove it.

Captions 25-26, Deutsche Sporthilfe - Ball des Sports

 Play Caption

Hans erklärte, er sei nicht verzaubert,

Hans explained that he was not bewitched,

sondern wirklich ein Igeljunge.

but really a hedgehog boy.

Caption 71, Märchen - Sagenhaft - Hans mein Igel

 Play Caption

Sie behaupteten, sie seien Weber eines seltenen,

They claimed that they were weavers of a rare,

besonders schönen Stoffes.

especially beautiful cloth.

Caption 25, Märchen - Sagenhaft Des Kaisers neue Kleider

 Play Caption

Further Learning
You will likely come across examples of reported speech on Yabla German from time to time, but structures like Sie sagt, dass er Italienisch spricht are simply more common in spoken German. When you do see an example that uses Konjunktiv I, check to see if it's a regular or irregular verb in terms of its conjugation. 

The Duden German Dictionary has the definition of the standard form of the adjective/adverb schräg as "deviating from a vertical or horizontal line at an acute or obtuse angle." With this standard meaning, schräg is usually translated into English as "diagonal" or "diagonally."

Sie lehnen den Kopf schräg nach links...

You'll turn your head diagonally to the left...

Caption 12, Nackenschmerzen - steifer Nacken

 Play Caption

In dem er sich senkrecht oder schräg positioniert,

By positioning itself vertically or diagonally,

lauert der Trompetenfisch seiner Beute auf.

the trumpet fish lies in wait for its prey.

Captions 47-48, Evolution - Meeresbewohner

 Play Caption

The second definition of schräg as a slang term is more interesting. Duden's definition describes schräg as "deviating from the norm, customary, or expected, and therefore unacceptable." In other words, "weird"—and not in a good way.

Although the German dictionary mentions that the slang usage of schräg is usually a pejorative or put-down, it does not give any examples of schräg used in a complimentary sense. In fact, the slang adjective—probably originally used as a put-down of jazz, experimental music, and modern art—eventually had its negative connotation turned on its head. By the late 1970s and early 1980s, with the advent of punk and industrial music, as well as increasingly "difficult" contemporary art, describing music or art as schräg was often meant as a compliment.

It might seem a bit tricky to tell if something somebody describes as schräg is meant as an insult or a compliment, but it's usually pretty easy to tell in context.

Alles frei nach dem Motto:

Everything freely according to the motto:

„Je schräger desto besser."

"the more eccentric, the better."

Caption 12, Auftrumpfen - Mit Kitsch und Protz

 Play Caption

Der war irgendwie psychisch ziemlich... schräg drauf.

Who was, in a way, quite psychologically... skewed.

-Angeschlagen.

-Damaged.

Caption 75, Sons of Sounds - Interview

 Play Caption

Die Kanzlerin auf einer vom schrägen Designer gepimpten Glitzer-Harley?

The Chancellor on a glittering Harley pimped out by the weird designer?

Caption 13, Stardesigner Harald Glööckler - Jetzt auch noch "Bling-Bling"-Motorräder

 Play Caption

Er fahre eigentlich Mercedes und kleide sich deshalb so schräg,

He actually drives a Mercedes and the reason he dresses so weirdly

weil er vor 20 Jahren Boris Blank getroffen habe.

is because he had met Boris Blank 20 years ago.

Captions 31-32, Yello-Biographie - Ein Leben für die Avantgarde

 Play Caption

The most common English translation of the slang meaning of schräg is "weird," but as you see above, there is a lot of latitude in translation, depending upon the context. The translation in the "Sons of Sounds" video as "skewed" is very clever, since it also acknowledges the translation of the standard meaning of schräg as "diagonal" yet still conveys the slang meaning!

Further Learning
Think of a concert or some kind of art event that you have attended that surprised you by being strange in a way that you liked. Make up a few sentences describing the event in a positive way using the slang meaning of schräg. Now think of some events you attended that were just too strange for you to like. Think up a few sentences describing these events in a negative way using schräg. Then go to to Yabla German and watch the full-length videos quoted above to get a better sense of the contexts in which schräg was used.