Alternativ zum Passiv
There are a few alternative constructions to the passive voice in German. The verb “lassen” is one of these, which means “to let”; however, it is used differently here than in English. Consider the following examples:
Es lässt sich leicht erklären. / It lets itself be easily explained. (literal translation)
The English translation sounds awkward to any native English speaker — the better equivalent is: “It is easy to explain” or “it can easily be explained.” The passive voice uses past participles in both English and German, but the above formulation is constructed using a present tense reflexive verb and an infinitive (lässt/erklären; is/to explain). This German alternative to the passive voice is used in place of the modal verb “können” in the passive (e.g. Es kann nicht geschrieben werden. = Es lässt sich nicht schreiben.). Below are some more examples to give you an idea of how “lassen” is used:
Ich lasse mich beraten. / I am going to get advised/seek advice.
Lässt du dein Fahrrad reparieren? / Are you going to get/have your bicycle repaired?
Much like in the previous examples, the English equivalents are not word-for-word translations, but they convey approximately the same meaning: in both cases, the subject is not the one doing the activity (beraten, reparieren); but rather, they are having someone else perform those services, i.e. they are arranging for them to be done.
Used as a reflexive verb, “lassen” can refer to letting/allowing something to be done:
Sie lässt sich operieren. / She is having surgery.
Sie lassen sich scheiden / They get/are getting divorced.
Er lässt seine Haare lang wachsen. / He is letting his hair grow out/long.
To put the verb “lassen” in the past tense, conjugate the helping verb “haben” and place the infinitive “lassen” after the infinitive form of the main verb, creating a double infinitive. For example,
Sie lässt sich operieren. = Sie hat sich operieren lassen.
Ich lasse mein Auto in der Garage stehen. = Ich habe mein Auto in der Garage stehen lassen.