Learn Turkish: Evet, bu kalem ucuz. - Yes, this pen is cheap.

In Turkish, the word for 'is' (for the third person, like 'he', 'she', or 'it') is often invisible. Just putting the adjective ucuz directly after the subject bu kalem is enough to mean 'this pen is cheap'.

Since this lesson is about değil, how would I make this sentence negative?

To say 'this pen is not cheap', you simply put değil at the very end of the statement. The negative version is Hayır, bu kalem ucuz değil.

Does kalem mean 'pen' or 'pencil'?

It means both! Kalem is a general word for any stick-like writing tool. If you need to be specific, a pencil is kurşun kalem (lead pen), but usually, just kalem works perfectly for either.

What happens if I change the word order to Bu ucuz kalem?

That changes the meaning from a full sentence to a noun phrase. Bu ucuz kalem means 'this cheap pen' (for example: 'I want this cheap pen'). Because ucuz is placed at the end in our actual sentence (Bu kalem ucuz), it completes the thought: 'This pen is cheap.'