These examples show that there are certain fundamental syntactic principles which govern the construction of sentences in all languages. However, these principles are flexible enough to allow distinctions among languages. For example, yes-no and information questions in English and Thai are formed by the two major structure-building mechanisms: the Merge operation and transformations. However, due to differences in the types of transformations that apply in the deep structure, the surface structure of the two questions in Thai is different from those in English.