Lay or lay down? - this question for the modern Russian language can be safely called eternal, because the word to lay down that does not exist in the Russian language occurs in colloquial speech much more often than to lay down correctly. And if such a verb touches the ear of language connoisseurs, then for most ordinary people it seems correct to say to lie down.
Often confusion arises with the use of such verbs in different tenses and forms, so let's try to figure out how to speak correctly and which verb to use in certain situations.
So, let's remember for a start that there is no verb to lay down (I lay down in the past tense and I will lay down in the future tense, respectively). We refuse to use such a word, and, if necessary, we use the verb only with prefixes (put, put, put, put, put, attach, attach).
Please note that the verbs mentioned above are used only in the past and future tense and have a perfect form.
The verb I put is used, as a rule, without prefixes. For example, there are no words for luggage in the literary language (however, there are such words as, shift, report, lay). The verb I put can be used in all tenses and it has an imperfect form: I put it, I put it, I will put it.
In other words, the verbs put, put and others should be used when an action in the past has already been performed or will be performed in the future, without an emphasis on its duration. For example, I put the pen on the table - the emphasis is on the pen resting on the table. The verb to put is used when the action has an imperfect form and the emphasis is on its duration in the past or future tense, or on the fact that the action continues at a given moment in time. For example, I put my pen on the table - the action continues now. Or, the second example, I laid a brick for three days - the sentence expresses the duration of the brick laying, while the sentence - I put the brick - would reflect the fact that the brick has already been laid.
So, the answer to the question: "How to speak correctly: put or lay down?" not as simple as it might seem, but the main thing is to remember two things:
1. There is no verb to lay down in Russian, it is used only with prefixes and reflects an action that has already been performed in the past or will be performed in the future.
2. The verb to put in most cases is used without prefixes in all tenses and reflects a continuous action that is taking place now, took place in the past or will occur in the future tense.