In the subjunctive mood there is absolutely no distinction of time between the tenses; the aorist tense does not refer to past time and the present subjunctive does not necessarily refer to present time. The distinction between the present and the aorist concerns merely the manner in which the action is regarded. The aorist subjunctive refers to the action without saying anything about its continuance or repetition, while the present subjunctive refers to it as continuing or as being repeated. Thus ἵνα λύσω means simply in order that I may loose, while ἵνα λύω means in order that I may be loosing, or the like. But ordinarily it is quite impossible to bring out the difference in an English translation. The present and the aorist subjunctive will usually have to be translated exactly alike. The student should use the aorist in the exercises unless he sees some reason for using the present, since the aorist presents the action in a simpler way, without any added thought of its duration.