We’ve already dealt with the semi-colon.

We’ll assume you correctly use commas and periods.

Just a quick word on question marks and exclamation marks.

Unless you are sitting in an online chatroom and want to express that you just spilt your drink all over your keyboard (for example “I just spilled my drink all over my keyboard!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!”), remember this:

Multiple exclamation marks or question marks are really NOT okay. (!)

The expression and power behind your statement should come from your words. Repeated exclamation or question marks not only dulls the effect, but displays an immature writing style.