Formal wording
Don't write like you speak! There are many differences between spoken and written language - some lexical (vocabulary) and some grammatical. One way to make your written language more formal is to use words that come from Latin rather than ones that come from Old English. Most technical or jargon words from your discipline are taken from Latin or ancient Greek (the word 'thesis' itself is from the Greek to 'set something down'), but there is often also choice with non-technical words between conversational and formal alternatives for the same basic thing. If you need help thinking of suitable alternatives and/or checking where your words come from, consult a good dictionary or thesaurus (and if you don't have one at home, find one in the library, or Online via a quick web search e.g. Google).
Consider the different word choices indicated in each version of this message.
Informal
Many people think that lots of Vietnamese people live around Cabramatta because they don't want to join in with the rest of society and only want to live around each other. Others say that they have no choice because of money, politics or society in general.
Formal
The Vietnamese concentration around Cabramatta in western Sydney is popularly conceived as the result of that migrant group choosing to avoid the wider society and remain in a secluded enclave. More theoretical and structuralist explanations blame external forces such as economic, social and political constraint for the segregation of ethnic minority groups.
Comment
- 'think' and 'believe' are from older forms of English, while 'consider' and 'conceive' came into English from Latin
- the meaning of 'lots of people' is conveyed more formally through 'concentration', another word from Latin
- many other words in the second version are from Latin or French
http://www.wordfocus.com
Another way to increase formality is to use the so-called 'passive voice'. The passive has many uses, but in terms of creating formality, it can help your writing sound more objective by fore-grounding the experimental work rather than the researcher/writer.
Note the difference between these versions of a message.
Active
We removed the elaiosomes from some seeds to see if they were more likely to be removed than seeds with elaiosomes. We carried out this experiment during January 1998 in the Royal National Park in a dry sclerophyll area. We set out a 100 m x 100 m plot with 80 depots in it. We used a random number table to put D. juniperina in half the depots and A. linifolia in the rest. We removed the elaiosomes from half of each of the species. We put 10 seeds in each depot and after 10 hours we counted how many seeds were gone.
Passive
A seed removal experiment was carried out to determine whether the removal of seeds with elaiosomes is more common than that of seeds from which the elaiosomes have been experimentally removed. The experiment was conducted during January 1998 in Royal National Park in dry sclerophyll vegetation. At this site a 100 m x 100 m plot was set out with 40 depots each of D. juniperina and A. linofolia seeds, which were placed out in a grid in random order using a random number table. For each species, 20 depots consisted of seeds with the elaiosomes removed while the other 20 depots consisted of seeds with intact elaiosomes. Each depot consisted of a small pile of 10 seeds. After 10 hours, the number of seeds removed per depot was recorded.
The academic skills support site, UniLearning has further information on formal language if you're interested.
Next: Impersonal wording 
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