Webb and Nation (2017:180)

Productive learning is more difficult than receptive learning, mainly because it requires more precise knowledge of aspects of the form, meaning, and use of words than receptive learning. It also requires the learners to give attention to aspects of vocabulary knowledge that are not so critical for receptive use.

Durrant (2016:50)

Wordlists are based on the premise that some words are likely to be more useful to learners than others.

N Schmitt (2014:914)

The exact nature of lexical knowledge has always perplexed researchers and teachers.

N Schmitt (2014: 940)

It is difficult to ... come to conclusions about the strength of the relationship between size and organization as vocabulary size grows.

N Schmitt (2014:941)

Vocabulary size (as measured by the VLT) and lexical organization (as measured by the WAF) are strongly related to each other.

Unaldi, Bardakci, Akpinar and Dolas (2013: 92)

Using mnemonics to teach/learn new words without any contexts looks like a new fad which is slowly turning into a commercial gimmick .. there are words that are very suitable for mnemonics, but generally their frequencies in the real language in use are really low and the corresponding meanings created in this way are often single and one dimensional.

Nation (2011:536)

Well directed deliberate vocabulary learning using word cards is very effective and much more efficient than teaching and vocabulary exercises."

Coxhead (2010:5)

High-frequency words need to be the main focus for learners initially and ... low-frequency words should be dealt with using a variety of strategies.

Webb (2008:93)

although the results of the present study might confirm that learners' receptive vocabulary size is larger than their productive vocabulary size, it is likely that this relationship varies from group to group.

Hyland & Tse (2007:247)

By breaking into single words items which may be better learnt as wholes, vocabulary lists simultaneously misrepresent discipline-specific meanings and mislead students.

Cunnigham (2005:46)

Even the most tailored and comprehensive instruction cannot shoulder all of the vocabulary learning that must take place in the school years and beyond.

Nagy (2005:34)

Having a big vocabulary does contribute to being a better reader. But being a good reader also contributes to having a bigger vocabulary.

Meara and Wolter (2004:87)

Vocabulary size is not a feature of individual words: rather it is a characteristic of the test taker’s entire vocabulary.

Qian and Schedl (2004:46)

...in terms of item difficulty level and power of predicting reading performance – the DVK [Depth of Vocabulary Knowledge] format is worth further evaluation as a basis for developing potential item types in the context of TOEFL 2000.

Gu (2003)

This (mnemonics) is an area that has received by far the most attention, so much so that I would even argue that it has turned into a classic case of overkill.

Gu (2003)

With the exception of a handful of studies in classroom contexts (Fuentes, 1976; Levin, 1979; Willerman & Melvin, 1979), two and a half decades of rigorous experimentation points to a single conclusion that the keyword method is superior to almost all other methods tested (e.g., rote repetition, semantic methods, or placing words in a sentence). These findings are so unanimous that another review here would appear redundant.

Richards and Renandya (2002:255)

Vocabulary is a core component of language proficiency and provides much of the basis for how well learners speak, listen, read, and write. Without an extensive vocabulary and strategies for acquiring new vocabulary, learners often achieve less than their potential and may be discouraged from making use of language learning opportunities around them such as listening to radio, listening to native speakers, using the language in different context, reading, or watching TV.

DeCarrico, J (2001:288-289)

Especially at the beginning levels, the teaching of word lists through word association techniques has proven to be a successful way to learn a large number of words in a short period and retain them over time.

Nation (2001:232

Incidental learning via guessing from context is the most important of all sources of vocabulary learning.

Fan (2000:105)

There was no evidence to indicate a consistent ratio between active and passive vocabulary knowledge and the relationship between them has been found to be more complicated than it appears to be.

Read (2000:149)

There is no perfect test and it is necessary to develop a whole range of instruments to address the various purposes for vocabulary assessment".

Schmitt (2000:55)

Lexical knowledge is central to communicative competence and to the acquisition of a second language.

Zimmerman (1997:5)

Vocabulary is central to language and of critical importance to the typical language learner.

Hatch and Brown (1995:422)

the key in all vocabulary teaching is to keep motivation high.

Laufer (1994:29)

the general tendency is for basic vocabulary to decrease and be replaced by a more advanced vocabulary.

Nation (1993:118)

The focus of teaching initially needs to be on increasing the size of the learner's recognition vocabulary."

Ryan (1993:245)

...the process of learning to read in English may present far deeper psycholinguistic difficulties for our Arabic learners than are normally appreciated.

Haastrup (1991:23)

In my view, it [inferencing] is a comprehension procedure that does not automatically lead to learning, although it has the potential for doing so.

McCarthy (1990:8)

No matter how well the student learns grammar, no matter how successfully the sounds of L2 are mastered, without words to express a wider range of meanings, communication in an L2 just cannot happen in any meaningful way.

Ahmed (1989:9)

Good learners not only use more strategies, but they rely more heavily on different strategies than the poor learners use.

Stein (1989:36)

The role of the dictionary in foreign language teaching is rarely discussed at all in the literature, and if it is, this is done in a rather cursory way.

Odlin (1989:77)

Similarities and dissimilarities in word forms, along with similarities and dissimilarities in word meanings, play a major role in how quickly a particular foreign language may be learned by speakers of another language.

Odlin (1989:79)

Learners may not always note the formal similarities that mark a cognate relation, and they may not always believe that there is a real cognate relationship.

Nation and Coady(1988:101)

Indeed the very redundancy or richness of information in a given context which enables a reader to guess an unknown word successfully could also predict that that same reader is less likely to learn the word because he or she was able to comprehend the text without knowing the word.

Nation and Coady(1988:104)

[Learners can] guess between 60% and 80% of the unknown words in a text if the density of unknown words is not too high.

Carter (1987:153)

.. quantities of initial vocabulary can be learned both efficiently and quickly and by methods such as rote learning which are not always considered to be respectable. It may be dangerous to underestimate such a capacity.

Saville-Troike (1984:199)

Vocabulary is the single most important area of L2 competence when learning content through that language.

Meara (1982:100)

This neglect [of vocabulary] is all more striking in that learners themselves readily admit that they experience considerably difficulty with vocabulary, and once they have got over the initial stages of acquiring their second language, most learners identify the acquisition of vocabulary as their greatest source of problems.

Brown, DF (1980:15)

If a student guesses correctly when he does consult the dictionary, he has the satisfaction of thinking ‘Ah yes, I was right!’ This is a reward feeling and builds confidence to guess another time. If the guess was wrong, still an effort was made and that in itself is better than being passive in the learning process.

Wilkins (1972:111-112)

While without grammar very little can be conveyed, without vocabulary nothing can be conveyed.

Firth (1957:11)

You shall know a word by the company it keeps.

Price (1929:5)

To get anything to stick in the minds of high school pupils it must be drilled over and over again, now in this form, now in that; it must be heard, must be spoken, must be seen, must be written; and worked over and over again and again; and even then half of it is forgotten from class to class and from year to year.