Forms of punctuation

The punctuation used in a research report must be consistent. Consistent punctuation and use of symbols makes the text easier to understand and read.

Numerical Expressions

Numerical punctuation includes the following principles:

  1. Separate a number from a unit of measurement/its abbreviation with a space 
  2. Numbers containing four or more digits must be separated into groups of three digits: 7 456 543. In decimals the numbers are grouped in threes after the decimal point: 3.123 32. 
  3. A numerical expression cannot start a sentence. 
  4. Two numbers expressing different issues cannot be placed one after the other in a text. 
  5. Dates are written day-month-year. There should not be any unnecessary zeros in front of numbers in dates: 2.3.2006 (the second of march, in the year two thousand and six).

Abbreviations and Symbols

Abbreviations make a text difficult to read and hinder communication. Use abbreviations sparingly or only make use of abbreviations that are in common use. The abbreviation e.g. can be used before lists or separate additions but not in the middle of a text.

When using abbreviations bear in mind that they should save time and space and are easy to interpret. The following principles are used when abbreviating:

  1. Compound nouns and word combinations are abbreviated from the first letter of each word in the compound with a full stop after it: etc. – et cetera, cf. – confer/compare with, e.g. – exempli gratia (for example). Abbreviations containing capital letters do not have a full stop: EU, USA; UN.
  2. When only the initials are used of first names, there must be a full stop after each first name initial and a space between initials: J. K. Paasikivi, U. K. Kekkonen. Compound names are written: V.-M. Loiri, M.-L. Seuna. Make sure that they are written correctly in your bibliography!
  3. Units of measurement are in common use and do not need a full stop: km, Mo, Tsp. There is a space between the unit of measurement and the abbreviation: 20 min.


In printed text a dash is used to express limits. There are no spaces on either side of the expression when the dash is of the correct length. In natural science or technical texts, a three dotted line can be used between the figures to avoid possible misunderstanding: -5…-20.

The semicolon is stronger in effect than a common but weaker than a full stop. It is used to divide long lists into subgroups when the comma is being used in the same list for a different purpose. In the source reference the semicolon is used to separate different writers (Hakulinen 1980, 73; Vilkuna 1992, 21).

The colon is used when referring to the next sentence containing an explanation, conclusion or justification. In this case such sentences can be linked using a comma, conjunction (since, because) or adverb (actually, in fact). If the colon only affects the clause as far as the full stop, the part after the colon begins with a small case letter – even if it is a full sentence. A capital letter is used after a colon when the colon introduces several sentences, e.g. an explanation.

A colon also separates

  1. the name of a work or piece of writing and more specific information (opetussuunnitelman toteutuminen: tutkimusprojektin lähtökohdat)
  2. the publishers location and the name of the publisher in the bibliography (Helsinki: Otava, Porvoo: WSOY)