The letter "X" is never used as the last group of the text.

In written correspondence a kiss has been represented by the letter "X" since at least 1763.

The color black and the letter X became signature motifs.

I put a firm letter X at each site.

The letter X is going to be a problem, I can see.

The wrists are crossed making a letter X, the left forearm on top of the right one.

Instead, it used the letter X to denote an unknown factor.

In human style it is represented by the letter "X".

He smiled gently, quickly drew the letter "X" in the air with his finger.

The person must refrain from clicking if they see the letter "X" presented.