Due to the diverse ethnic mix in Singapore, there are four languages in common usage - Malay, Mandarin Chinese, Tamil and English. English is widely used as the 'common' language because of its apparent neutrality as well as its importance in the international business arena. Many Singaporean schools run the curriculum in English. Therefore, levels of English are extremely good in Singapore and foreign business people who also have a good command of the English language will have little difficulty communicating.
However, good communication and mutual comprehension often require more than a common language and many misunderstandings flow from differing concepts of the appropriate or inappropriate use of language.
As in many Asian cultures, 'no' is a difficult word and other ways of expressing disagreement should be sought. Disagreement can affect the harmony of the situation as well as possibly making somebody lose face and needs to be avoided. Vagueness and substitutions are often used to avoid disagreement. Thus 'no' becomes, 'Yes, but it might be difficult' and 'yes' might merely imply 'I have understood your point.' It is therefore important that everything, which is said, is not taken literally. Ask lots of open questions and go over important points several times. However, should your probing reveal a flaw in the logic of an argument or an actual mistake, try not to point it out in public. Be aware of the 'face' of the other side.
Humour can often be misunderstood or not understood at all and as such is best avoided. It is better to underplay your personal merits, majoring rather on the merits of your organisation or department. Conversation about deeply personal issues should be avoided, as should comments about the Singaporean 'system'.