The term "Imperativus Pro Infinitivo" (often abbreviated as IPI) refers to a grammatical construct in Latin where the imperative mood is used in place of an infinitive. This usage typically serves to express commands, requests, or obligations in a way that would usually be conveyed with an infinitive form. In many instances, this construction can occur in indirect speech or in contexts where a more direct command is preferred.

Coreference is a linguistic phenomenon in which two or more expressions in a text refer to the same entity or individual. For example, in the sentences "Lisa went to the store. She bought some groceries," the pronoun "she" is a coreferential expression that refers back to "Lisa.

Interactional linguistics is an interdisciplinary field that studies how language functions in social interactions. It combines insights from linguistics, sociology, conversation analysis, and discourse analysis to explore how people use language in real-time communication. The focus is often on the nuances of spoken interaction, including the ways in which language constructs social meaning, identity, and relationships among speakers.

The term "nearest referent" is often used in the context of linguistics, semantics, and discourse analysis. It refers to the closest entity or concept that a pronoun, demonstrative, or other referring expression points to within a given context.

Attributional calculus, often referred to in the context of reasoning and inference systems, is a formal framework used to model and manipulate complex relationships between events, entities, or concepts. Although not a widely recognized term in standard mathematical literature, the concept can generally relate to reasoning about causation and the attribution of causes and effects within a logical framework.

Phi features, often referred to in the context of genetic modifications or advanced biotechnology, can represent a variety of concepts depending on the specific field of study or application. However, in a general sense, "Phi features" might not refer to a widely recognized or established concept as of my last training cut-off in October 2023.

Phrase structure rules, also known as rewrite rules, are a set of formal grammatical rules used in generative grammar to describe the structure of phrases and sentences in a language. These rules define how symbols (which can represent words, phrases, or other grammatical constructs) can be combined to form larger grammatical units. The basic idea is that phrases can be generated from smaller constituents based on these rules.

Pseudogapping is a syntactic phenomenon in linguistic theory, particularly within the field of generative grammar. It involves a type of ellipsis where part of a verb phrase (often including a verb and certain complements or adjuncts) is omitted, while some parts remain overt. This results in a structure that gives the appearance of a gap but does not neatly fit into traditional ellipsis patterns like gapping or sluicing.

Dynamic semantics is a theoretical approach to understanding the meaning of linguistic expressions that focuses on how context and discourse evolve over time during communication. Unlike static semantics, which views meaning as fixed and derived from the lexical and grammatical properties of expressions alone, dynamic semantics considers how the meaning of sentences can change based on the discourse context and how they interact with previous statements.

Dubnium is a synthetic chemical element with the symbol Db and atomic number 105. It is named after Dubna, a town in Russia where the Joint Institute for Nuclear Research is located, and where the element was first synthesized in 1968 by a team of Russian and American scientists. Dubnium is a member of the actinide series, and it is placed in the d-block of the periodic table's group 5, which makes it part of the transition metals.

Lawrencium is the chemical element with the symbol Lr and atomic number 103. It is classified as a synthetic element and belongs to the actinide series of the periodic table. Lawrencium was first synthesized in 1961 by a team of scientists at the University of California, Berkeley, and it was named in honor of Ernest O. Lawrence, the inventor of the cyclotron.

This is quite in-depth, pretty good.

Unrelated to the Khan Academy.

Maybe Spanish accent, but might also be from some other european language.

Very practical, low-cost experiments.

Falls a bit too much on the basic side of the the missing link between basic and advanced.

This is very promising.

Ciro Santilli's answer to How credible is Nick Lucid, of YouTube's "The Science Asylum"? on Quora.