Two symbols called the en dash and the em dash resemble the hyphen but are used for different purposes. En dashes ("–") are slightly longer than a hyphen, while em dashes ("—") are even longer. In informal writing, you can usually get away with using hyphens and dashes interchangeably, but in formal contexts, you'll want to keep the uses of each distinct, as it can be considered a grammar error to do so. Following these general rules can help you keep your use of hyphens and dashes distinct. Below are a few of the situations in which you'll need to use dashes:  Ranges of dates, numbers, times, and values (en dashes) Prefixes for words which don't usually have them (en dashes) Substituting for blank or missing content (em dashes) Abrupt sentence interruptions (em dashes) Punctuating a sentence with extra information (em dashes) En dashes are often used to express the idea that two or more words or numbers are connected by a range of values in between. For instance, in the sentence "We just delivered the Jan–Apr issue," the dash implies that the magazine is for January through April, not just January and April. Note that when using en dashes for ranges, you shouldn't put a space on either side of the dash. Here is an example of an en dash used to express a range:Would you please schedule me an appointment for 1:00–2:00 PM? In general cases, you shouldn't use any sort of punctuation mark for common prefixes like "pre-", "post-", "re-", and so on. However, when connecting this sort of prefix to a word like a proper noun, a complex phrase, or a word that would look awkward or cumbersome without some  sort of separating mark, it's acceptable to use an en dash. Obviously, however, en dashes shouldn't be used for words like "preselect" or "postgame" where the meaning is already clear. Here are a few examples of en dashes used to attach prefixes:The professor's degree in the pre–Cold War history of Russia qualified him to teach his course on Czar Nicholas II. Post–Andy Kaufman, the comedy landscape just didn't seem as vivid. Em dashes can be used to abruptly break the flow of a sentence to convey related information, add commentary, and more. Em dashes used in this way can either come before the words inserted into the middle of the sentence or before and after them if the original sentence continues after the interruption. Unlike typical hyphen and dash usage, some grammatical resources allow you to separate em dashes from the rest of the sentence with spaces when used this way. Below are a few examples of em dashes used to interrupt sentences: Deborah — who was nineteen — still loved the swings at the local park. There's no need to lock the door — I'm coming out after you. Em dashes can also be used at the end of a sentence to  show that the flow of words has abruptly ceased before the sentence would normally have ended. In this case, you shouldn't end the sentence with a period, question mark, or exclamation point as you normally would. This is an especially useful tool for written dialog, as it allows you to show when one character interrupts another by speaking over him. Here's an example of an em dash being used to show someone's speech being interrupted: Where are we going? The police are right --—" "Shh! They'll hear you." In some cases, when information is intentionally left out, it's acceptable to use one or more em dashes to substitute for the missing words or letters. Often, this is used in citations: some style guides call for three em dashes to be used in place of an author's name when it needs to be listed many times in a row. This can also be used to "censor" the names of people or places to keep them confidential. Here is an example of an em dash being used to substitute for missing information:The paranormal incident took place in the night sky just outside of the rural town of N——.

Summary: Know when to use a dash instead of a hyphen. Use en dashes to describe ranges. Use en dashes to attach prefixes to awkward words or phrases. Use em dashes to punctuate a sentence. Use em dashes to show when a sentence cuts off. Use em dashes to substitute for missing information.


Before you assemble the back-drop, measure its length and width. Mark the dimensions of the back-drop with a light pencil mark, chalk, or a piece of tape. The back-drop may be as large or as small as you’d like—it will really depend on the space you’re using and how you intend to capture the back-drop on camera. Ask yourself the following questions: Do you want to take full-body shots or will the pictures be from the waist up? How tall are your guests? How many guests do you want in one picture? Stretch a piece of masking tape—sticky side out—along the top edge of your back-drop from corner to corner. To secure the tape to the wall, cover each end with a piece of masking tape. The streamers will hang from the sticky side of the tape. Attach streamers to the masking tape from left to right. Roll out each streamer to the desired length and cut it in a straight line. As you move from one corner of the back-drop to the other, layer the streamers slightly and vary the colors. Don’t worry about cutting every streamer to the same length. You will trim them later. Place pieces of rolled masking tape along the top edge of the back-drop. Roll a single streamer along the top edge of the back-drop in a straight line. Cover the two small vertical pieces of tape on each end in the same manner. This will give the top of your back-drop a clean, crisp edge. Stretch a piece of masking tape—sticky side in—across the bottom edge of your back-drop. Attach each end of the tape directly to the wall. This piece of tape will prevent your streamers from moving. If you want the streamers to move with the breeze, don’t tape the streamers to the wall. This will provide you with a less structured, and perhaps more whimsical backdrop. With a pair of scissors, carefully trim each streamer near the bottom edge of the tape. You will cover the bottom with a streamer, so don’t worry about trimming each streamer perfectly. Stick several pieces of rolled masking tape along the bottom edge of your back-drop. Roll a single streamer along the taped edge in a straight line. When the backdrop is done, you will have a solid rectangle or square of crepe paper to pose in front of. You can add two small vertical streamers to each corner so that it matches the top.
Summary: Determine the dimensions of your back-drop. Attach a piece of masking tape—sticky side out—to the wall. Stick streamers onto the tape. Cover the top edge with a piece of crepe paper. Tape the bottom of the streamers to the wall. Trim the streamers just below the edge of the tape. Cover the bottom edge with a piece of crepe paper.