㈣避免用代名词“they, you, it”影射脑子里的事物，如：
⑨ In Singapore, it relies heavily on tourism as a source of national revenue.
这里的 it 指向什么呢?如果是心目中的“政府”或“旅游促进局”，那就要明言，不要用不清不楚的 it：
⑩ In Singapore, the government……
11. In Singapore, the Tourist Promotion Board……
12. In less industrialised countries, they do not know the problems of urban development.
这里的代名词 they 是不是指 the people(人民)?如果是就用吧。In less industrialised countries, the people……过后，要再提这主语时，才用 they：……the people……They are only interested in their daily life.
其实，在这种主语不详的情况下，被动语态是最好的选择：
13. In less industrialised countries, the problems of urban development are not known
