During all this time, according to Curtius, our Aryan language would have consisted of nothing but roots, used for nominal and verbal purposes, but without any purely derivative suffixes, whether verbal or nominal, and without declension. The only advance, in fact, made beyond the purely Chinese standard, would have consisted in a few combinations of personal pronouns with verbal stems, which combinations assumed rapidly a typical character, and led to the formation of a skeleton of conjugation, containing a _present_, _an aorist_ with an augment, and a _reduplicated perfect_. Why, during the same period, nominal bases should not have assumed at least some case-terminations, does not appear; and it certainly seems strange that people who could say +vak-ti+, speak-he, +vak-anti+, speak-this-he, should not have been able to say +vâk-s+, whether in the sense of speak-there, _i.e._, speech or speak-there, _i.e._, speaker. The next step which, according to Curtius, the Aryan language had to make, in order to emerge from its purely radical phase, was the creation of bases, both verbal and nominal, by the addition of verbal and nominal suffixes to roots, both primary and secondary. Curtius calls this fourth the Period of the _Formation of Themes_. The suffixes are very numerous, and it is by them that the Aryan languages have been able to make their limited number of roots supply the vast materials of their dictionary. From +bhar+, to carry, they formed +bhar-a+, a carrier, but sometimes also a burden. In addition to +bhar-ti+, carry-he, they formed +bhara-ti+, meaning possibly carrying-he. The growth of these early themes may have been very luxuriant, and, as Professor Curtius expresses it, chiefly _paraschematic_. It may have been left to a later age to assign to that large number of possible synonyms more definite meanings. Thus from φέρω, I carry, we have φορά, the act of carrying, used also in the sense of _impetus_ (being carried away), and of _provectus_, i.e., what is brought in. Φορός means carrying, but also violent, and lucrative; φέρετρον, an instrument of carrying, means a bier; φαρέτρα, a quiver, for carrying arrows. Φορμός comes to mean a basket; φόρτος, a burden; φορός, tribute. All this is perfectly intelligible, both with regard to nominal and verbal themes. Curtius admits four kinds of verbal themes as the outcome of his Fourth Period. He had assigned to his Third Period the simple verbal themes ἐσ-τί, and the reduplicated themes such as δίδω-σι. To these were added, in the Fourth Period, the following four secondary themes:-- (1) πλέκ-ε-(τ)-ι Sanskrit +lipa-ti+ (2) ἀλείφ-ε-(τ)-ι „ +laipa-ti+ (3) δείκ-νυ-σι „ +lip-nau-ti+ (4) δάμ-νη-σι „ +lip-nâ-ti+. He also explains the formation of the subjunctive in analogy with bases such as +lipa-ti+, as derived from +lip-ti+. Some scholars would probably feel inclined to add one or two of the more primitive verbal themes, such as