These/those are the plural forms of this/that, and behave in the same way. As a determinerthis is used to identify a specific person or thing close at hand or being experienced. As a determiner that refers to the more distant of two things near to the speaker, or to a specific thing previously mentioned.
For example, in context of the sentence:
Sonny has many qualities worth recognizing, and the purpose of this letter is to point out two of [these/those] qualities.
these would be best.
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So speak tends to be used for one-sided communications (e.g. she spoke to her employees), whereas talk implies a conversation or discussion between two or more people (e.g. everyone was talking when he walked into the room). Speak is a little more formal than talk, and is often used in polite requests.
For example, eg. May I speak to the manager?
Lire PlusSavez-vous que d'apprendre une langue étrangère est très bien pour la réserve cognitive?
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