In the past the ending is "is": mi parolis, I spoke, etc.
In the future "os" mi parolos, I shall speak, etc. In the conditional "us": mi parolus, I should speak, etc. In the subjunctive "u": ke mi parolu, that I may or might speak, the tense being sufficiently indicated by the antecedent verb.
For the imperative we use the subjunctive without conjunction and generally without subject.
The participle has a most ingenious flexbility,
it having three forms, anta, inta, onta for the active, and ata, ita, ota for the passive; parolanta, speaking now; parolinta, having spoken; parolonta, about to be speaking; parolata, being spoken now; parolita, spoken formerly; parolota, to be spoken later.
Only practice can reveal the wonderful usefulness of this scheme, again, of course, applicable to all verbs.
One interesting sequel is, that as every word can be turned into a noun—if sense demands it—by simply changing the ending into o, we therefore get: parolanto, the present speaker; parolinto, the past speaker; parolonto, the future speaker.
Let no one say that such richness and possibility of precision is of no importance; many a life's jeopardy has turned on less. Nor can it be said that this unlimited capacity of expression makes the mechanism of the language cumbersome, for the whole scheme of Esperanto can be thoroughly mastered in a few hours.
([10]) In England Esperanto has been on the school rates for several years; any technical or continuation school can apply to the board of education for permission to put Esperanto on its program. In 1909 it was already thus taught in 33 centers.
The London Chamber of Commerce holds examinations in Esperanto every year, and has done so since 1907. The United Kingdom Association of Teachers prepares for the certificate of proficiency in Esperanto.